Pollutants doi: 10.3390/pollutants6020025

Authors: Mohammad Mehedi Hasan Ahsan Habib Mohammad Jahirul Alam Saiful Islam Ershad Halim

In the original publication [...]

Pollutants doi: 10.3390/pollutants6020024

Authors: Yanying Zhang Zheng Chen Deng Yang Qiuyue Sun Zhuoxin Yin Yuanyuan Shen Xiaoxiao Liu Guohua Chang Xisheng Tai Tianpeng Gao

Based on data from the literature in the Web of Science (WOS) and Scopus databases, this study collected 325 articles published between 2020 and 2025. Using Citespace software (version 6.4) to analyze publication volume, countries, institutions, disciplinary categories, and keywords, we examined research characteristics, hotspots, and bottlenecks in the field of ecological remediation for heavy metal pollution in mining area soils. Results indicate: (1) Publication volume in this field showed an upward trend from 2020 to 2024, accounting for 70.2% of this dataset being from the environmental sciences. Chinese scholars demonstrated significant dominance and high engagement, though interdisciplinary depth remained insufficient; (2) from 2020 to 2025, the research focus shifted from risk identification to precise remediation, forming a complete logical chain of ‘identification–remediation–optimization’. Green technologies (biological/combined remediation) emerged as mainstream approaches in integrated remediation. (3) A significant gap exists between research and practice. Many innovative technologies are costly and difficult for enterprises to bear, while low-cost techniques like ‘waste-to-waste treatment’ lack sufficient research and application, hindering large-scale implementation. This study reveals the current situation of ‘intense research but difficult application’ in the ecological remediation of heavy metal-contaminated soils in mining areas. The findings provide a scientific basis for technological innovation, practical implementation, and policy making.

Pollutants doi: 10.3390/pollutants6020023

Authors: Tejaswi Boyapati Sumit Ragho Gawai Pradeep Kumar

Microplastic (MP) contamination has become a global environmental and public health concern due to the extensive use of plastics and ineffective waste management. These microscopic particles are now detected in air, water, soil, and food products, raising serious concerns about their persistence, bioaccumulation, and potential risks. Microplastics (MPs) have been shown to disrupt marine biodiversity, affect plant metabolism, and enter food webs, leading to accumulation in human tissues. Chronic exposure is increasingly linked to reproductive toxicity, carcinogenesis, neurotoxicity, and metabolic disorders. This review provides a comprehensive overview of the sources, pathways, and environmental fate of microplastics, with an emphasis on their ecotoxicological effects and human health implications. It also summarises key analytical methods for detecting microplastics in environmental and food matrices, including spectroscopy, microscopy, and emerging sensor-based technologies. Finally, the review highlights the need for improved waste management, stronger policy interventions, and enhanced public awareness to mitigate microplastic pollution and protect ecosystem and human health.

Pollutants doi: 10.3390/pollutants6020022

Authors: Hamza Labjouj Loubna El Joumri Najoua Labjar Ghita Amine Benabdallah Samir Elouaham Hamid Nasrellah Brahim Bihadassen Souad El Hajjaji

Morocco’s recent legalization of industrial and medicinal cannabis has created a rapidly expanding seed-oil sector whose sustainability has yet to be fully assessed. This study applies an environmental life cycle assessment (LCA) in accordance with ISO 14040:2006 and ISO 14044:2006, complemented by a qualitative social responsibility assessment based on ISO 26000:2010, aiming to evaluate the life cycle sustainability of Moroccan cannabis seed oil. Three representative processing chains, traditional artisanal presses, producer cooperatives and regulated industrial plants are compared using a functional unit of 1 kg of cold-pressed oil packaged for local distribution. Inventory data were drawn from field measurements and interviews and were modeled in OpenLCA with background datasets from Ecoinvent 3.8 and Agribalyse v3.1. Impact assessment used the ReCiPe 2016 (H) method at the midpoint level across nine categories (climate change, fossil resource scarcity, water use, freshwater eutrophication, terrestrial acidification, land occupation, carcinogenic, non-carcinogenic human toxicity, and fine particulate matter formation). Sensitivity analyses varied seed yield, electricity mix and transport distances by ±20% to gauge uncertainty. Results show that the cooperative scenario achieves the lowest impacts across nearly all categories because of higher extraction yields (3 kg seed per kg oil), lower energy use (0.54 kWh kg−1 oil) and more effective co-product recovery. In contrast, artisanal extraction requires approximately 1 kg of additional seed input per functional unit compared to optimized scenarios, significantly increasing upstream environmental burdens and causing upstream agricultural burdens to multiply. Industrial facilities perform comparably to cooperatives if powered by renewable electricity. Integrating a semi-quantitative social responsibility assessment reveals that legalization has markedly improved organizational governance, labor conditions, consumer protection and community involvement. Cooperatives display the most balanced social performance, whereas industrial plants excel in governance and quality control. A set of recommendations, including drip irrigation, cultivar improvement, co-product valorisation, renewable energy adoption, eco-designed packaging and cooperative governance, is proposed to enhance the environmental and socio-economic sustainability of Morocco’s emerging cannabis seed-oil industry.

Pollutants doi: 10.3390/pollutants6020021

Authors: José Gonçalves João Pequeno Davor Krzisnik Paula Sobral Joana Antunes

Nanoplastics (NPs, <100 nm) have emerged as nano-scale contaminants with superior mobility and biological barrier-crossing capacity, yet risk assessment fails due to unstandardized analytical methods and a lack of realistic exposure data. This perspective proposes an “Exposome–Microbiome–Immune” (EMI) framework as a One Health paradigm to integrate detection, toxicokinetics, and systemic effects. We prioritize the following actions: (i) validated nano–Fourier transform infrared spectroscopy (nanoFTIR) and surface-enhanced Raman spectroscopy (SERS) for environmental/human monitoring; (ii) multigenerational studies in zebrafish and organoids; (iii) longitudinal cohorts for biomonitoring. Without shifting from descriptive reviews to systems toxicology, NP risk will remain underestimated.

Pollutants doi: 10.3390/pollutants6020020

Authors: Laura Romero-Zerón Rheya Rajeev Denis Rodrigue

Micro- and nano-plastic pollution caused by the mismanagement of plastics waste is a significant problem worldwide, causing severe impacts in aquatic and terrestrial environments. The purpose of this study was to evaluate the adsorption capacity of a thermally stable and superhydrophobic bio-substrate to remove microplastic particles (MPPs) from aqueous systems. In this work, the adsorption efficiency of cattail fluff towards MPPs from pristine PP, PVC, PA6, LDPE, HDPE, and their blend was evaluated. The effect of temperature (30 °C, 40 °C, and 50 °C) and two binding environments (distilled water and industrial wastewater) on adsorption was determined. Non-linear regressions of seven adsorption isotherm models including Langmuir, Freundlich, Temkin, Dubinin–Radushkevich (D–R), Redlich–Peterson (R–P), Toth, and Sips were applied to fit the experimental data. Error function analysis confirmed that the D–R adsorption isotherm model offers the best fit of the experimental data. The results show that the bio-substrate is very effective in adsorbing MPPs from aqueous systems with adsorption capacities of qe = 3597 mg/g and qe = 2807 mg/g in distilled water and synthetic industrial water, respectively. The composition of the MPPs determines the effect of temperature and binding environment on the adsorption performance of the bio-substrate. Physisorption dynamics for the MPP/bio-substrate system are also provided and discussed. Overall, the hydrophobic bio-substrate is highly effective in removing MPPs from aqueous systems, with the added advantages of low cost, sustainability, and scalability for practical applications.

Pollutants doi: 10.3390/pollutants6010019

Authors: Francesco D’Amico Daniel Gullì Ivano Ammoscato Teresa Lo Feudo Maurizio Busetto Claudia Roberta Calidonna

Air pollution is among the key topics in environmental policies and mitigation policies. Governments and institutions worldwide are working towards a better understanding of the phenomenon and means to reduce its impact on the environment and human health. In early 2020, the COVID-19 pandemic forced many countries to introduce strict regulations, effectively stopping non-essential anthropic activities. Italy had a pioneering role in this regard, anticipating other countries in Europe and across the world. These exceptional circumstances caused the concentrations of pollutants in the atmosphere to reach lower levels, thus allowing researchers to evaluate a number of hypotheses concerning the contribution of anthropogenic emissions. At the Lamezia Terme (code: LMT) World Meteorological Organization—Global Atmosphere Watch (WMO/GAW) regional station in Calabria, Italy, previous research highlighted the effects of governmental restrictions on the concentrations of gases (carbon monoxide, CO; carbon dioxide, CO2; methane, CH4, nitrogen oxides, NOx) and aerosols (black carbon, BC). In this work, sulfur dioxide (SO2) and ozone (O3) are also evaluated and all parameters are subject to the analysis based on the O3/NOx ratio, the ONRPI (Ozone to Nitrogen Oxides Ratio Proximity Indicator), which has been widely used at LMT to verify the balance between local and remote sources of emission. The implementation of this method to the first 2020 COVID-19 lockdown in the country has allowed significant improvement in our understanding of the variability of all evaluated parameters at the site, assessing with greater detail weekly cycles and day–night contrasts, and the influence of local and remote sources of emission.

Pollutants doi: 10.3390/pollutants6010018

Authors: Goutam Saha Amit Kumar Saha Awnon Bhowmik

Microplastics (MP) are transported through rivers, acting as major conduits to oceans, yet standard transport models often fail to capture polymer-specific dynamics like settling and removal. This study proposes two novel analytical frameworks to address this: a modified Advection–Dispersion Equation (ADE) incorporating first-order sinking and removal, and a multi-phase model accounting for hydrodynamic–particle coupling. We derived exact closed-form solutions for a finite pulse input and validated the baseline model against established results. Our results demonstrate that the conventional ADE significantly overestimates peak MP concentrations, while the modified ADE reveals a “stretching” effect that extends the duration of ecosystem exposure. Our analysis indicates that sinking is the primary driver of mass loss to sediments, with higher sinking rates reducing aqueous concentrations by approximately 50% compared to non-settling scenarios. However, removal employs negligible influence during the initial pulse phase but shows cumulative impact over long transport distances. The study highlights the critical need to incorporate sediment accumulation terms into risk assessments, as ignoring sinking leads to underestimating benthic pollution and overestimating marine flux. Additionally, the multi-phase formulation provides a theoretical basis for modeling dense plastic spills where particles alter flow momentum.

Pollutants doi: 10.3390/pollutants6010017

Authors: Athanasios Manouras Michalis Koureas Ermioni Meleti Ioannis Maisoglou Vasileios Manouras Eleni Malissiova

Maize is highly vulnerable to aflatoxin contamination, constituting a serious food safety and public health concern. This study explored the relationship of extreme flood events in September 2020 (Storm Ianos) and September 2023 (Storm Daniel) in the Thessaly region, Greece, which occurred post-harvest, and aflatoxin contamination patterns in maize harvests of both the flood years and the following years (2021 and 2024). A total of 573 maize samples collected between 2019 and 2024 were analyzed using an enzyme-linked immunosorbent assay (ELISA). A 10 μg/kg cutoff was used (the ELISA upper limit of quantification); results > 10 ppb were classified as elevated concentrations. Overall, aflatoxins were detected in 47.8% of samples, with 14.0% having concentrations exceeding 10 μg/kg. The 2021 harvest year exhibited an exceedance rate of 28.75% (23/80), while the 2024 harvest showed a rate of 14.68%, 37/252. Exceedance rates during flood years were comparatively low; however, the maize harvested in the years following the flood events demonstrated a two-fold increase in the detection rate (60.2% vs. 30.7%) and a significant increase in exceedance percentages (18.07% vs. 8.30%) relative to non-flood years in the preceding period. While drought and heat remain the primary field risk factors for aflatoxin production, the correlational findings suggest that extreme floods may indirectly influence aflatoxin risk by increasing kernel damage, prolonging grain moisture, and disrupting post-harvest handling and storage, underscoring the need for continuous monitoring and robust mitigation strategies in flood-prone agricultural regions.

Pollutants doi: 10.3390/pollutants6010016

Authors: George F. Antonious Basanta Neupane Edward K. Bordoh Mohammad H. Dawood

The undegradable characteristics of heavy metals on environmental quality have become a serious human health concern. A study was conducted in a potato field to investigate the impact of soil amended with animal manure or biochar on the transport of toxic heavy metals and nitrates to runoff and seepage water. The soil in 18 field plots was separated, and each of 3 plots was mixed with biochar, chicken manure, vermicompost, sewage sludge, or cow manure, with 3 plots used as the control. Following a natural rainfall event, the impact of soil treatments on the runoff and infiltration water volume was monitored. Runoff water from the soil amended with biochar exhibited 10.6 L plot−1, whereas cow manure exhibited 4.1 L plot−1, indicating about 61% reduction in runoff water volume. The vermicompost-amended soil increased the seepage water volume from 1.6 L plot−1 in the control treatment to 4.4 L plot−1, indicating a 175% increase in percolating water, a desirable attribute to direct rainfall water towards the plant roots. The concentrations of Pb, Cd, Ni, Mn, Cr, Mg, Cu, and K in infiltration water were greater in runoff sediments, highlighting the need for runoff sediment remediation technology.

Pollutants doi: 10.3390/pollutants6010015

Authors: Bonface O. Manono Zipporah Gichana Alice Theuri Kelvin Mutugi Kithaka

Nano- and microplastics (NMPs), which are ubiquitous environmental pollutants, are commonly found in single-use plastic water bottles. They originate primarily from the bottle material itself with the amount increasing through mechanical wear. This review synthesizes current scientific knowledge on the occurrence, health risks, and regulatory considerations concerning NMPs in single-use plastic water bottles. The review revealed that concentrations vary widely, leading to potential human exposure risks. Ingested NMPs can induce oxidative stress, inflammation, disruption of gut microbiota and potential bioaccumulation. Current health risk assessments are challenged by inconsistent methods and lack of standardized reference materials. While regulatory frameworks addressing NMP contamination are developing globally, they lack consistency and legally enforceable limits. Standardized detection and monitoring are emerging priorities, but legally enforceable limits and comprehensive policies are underdeveloped. This review highlights an urgent need for consistent regulations, standardized analysis methods, and research that examines realistic human exposure and toxicological impacts. To safeguard consumer health amidst escalating plastic utilization, it is essential for policymakers, researchers, industry, and public health stakeholders to coordinate their efforts to mitigate NMP contamination in single-use plastic water bottles.

Pollutants doi: 10.3390/pollutants6010014

Authors: Rasoul Adnan Abbas Mohammad Najafi Shima Zare Sevda Jannatdoust

Aging underground pipeline infrastructure across the United States, including systems used for potable water supply, wastewater collection, and stormwater conveyance, has exceeded its intended service life, emphasizing the need for replacement or rehabilitation to maintain reliable service to communities. Among available trenchless technologies, cured-in-place pipe (CIPP) is widely applied because it minimizes surface disruption and is well-suited for use in densely populated areas. Despite these advantages, environmental concerns remain regarding the release of total volatile organic compounds (VOCs) during CIPP installation and curing. This study evaluates total VOC emissions from CIPP liners under field conditions. Air samples were collected at six installation sites across the United States before, during, and after installation and curing to quantify key VOC species. Multiple sampling methods were employed, including photoionization detectors (PIDs), Summa canisters, and personal worker sampling. The measured compounds included styrene, cumene, acetophenone, hexane, toluene, and ethanol. Measured concentrations were compared with occupational exposure limits established by the U.S. Environmental Protection Agency (USEPA), the National Institute for Occupational Safety and Health (NIOSH), and the Occupational Safety and Health Administration (OSHA). The results indicate that styrene was the dominant compound within active CIPP work zones, with peak concentrations reaching 25.5 ppm during curing. In contrast, VOC concentrations decreased substantially within five feet downwind of the work zone. Overall, the findings suggest that potential public exposure risks are limited, while workers directly involved in CIPP operations may experience elevated short-term exposures during installation and curing activities.

Pollutants doi: 10.3390/pollutants6010013

Authors: Claudia Jantea Carmen Roba Maria Bizău-Cârstea

This study focused on the presence of heavy metals in the mining waste dump in the Certej area (Hunedoara County, Romania). The total content of metals (Cr, Cd, Cu, Mn, Pb, Ni, Zn, Fe) and the physical–chemical parameters (pH, redox potential, electrical conductivity, total dissolved solids, and salinity) were analyzed in the soil and sterile samples. The content of Cd, Cu, Zn, Pb, Mn in the samples collected nearby the mining waste dump was relatively low, being close to those considered normal levels in the national legislation. The samples from the mining waste dump indicated that Pb exceeded the alert levels, Zn almost reached the alert limit, and Cu exceeded the normal threshold. The content of Cd, Cu, Zn and Pb had an increasing trend from the top to the base of the dump, which may indicate a metal leakage due to water infiltration. Since agricultural activities take place in the proximity of the investigated area, special attention for plant uptake was taken into consideration.

Pollutants doi: 10.3390/pollutants6010012

Authors: Nikolaos Simantiris Nikos Karatzas Dimitra Papadoiliopoulou Martha Z. Vardaki

Ghost nets are the result of fishing nets ending up at sea by fishing vessels during operations, repairs, accidental loss, and from aquaculture activities. This is a major threat to the marine environment due to the entrapment of marine species, which often leads to the mortality of important species, the alteration of the marine benthic habitat, and the release of microplastics. In the current study, the authors conducted underwater clean-up activities in the marine protected area of Sounio in Greece (NATURA2000) to identify, evaluate whether they can be removed, and remove ghost nets. A total of 1200 Kg of ghost nets was removed within one year, with 68 different species reported to have colonized the nets. The reported groups were Mollusca, Porifera, Chordata, Arthropoda, Echinodermata, Bryozoa, Ochrophyta, Tracheophyta, Rhodophyta, Cnidaria, Chlorophyta, and Annelida. The species were not listed as threatened by the IUCN conservation status, while 86% were native, and 14% were invasive in the Mediterranean Sea. The current work presents the need to expand research efforts in the field of underwater plastic pollution, implement monitoring campaigns to a greater extent in the study area, and perform an assessment before the removal of ghost nets.

Pollutants doi: 10.3390/pollutants6010011

Authors: Agnieszka Anna Machnowska Krystyna Skwarlo-Sonta

The simplest definition of light pollution (LP) is the presence of artificial light at night (ALAN) at inappropriate times, intensity, and inappropriate amounts and colors. All these parameters of anthropogenic light clearly indicate that the presence of ALAN can disrupt the proper functioning of not only humans but all organisms on Earth that have evolved in conditions of alternating day and night, closing within a 24 h day. Cities are the primary source of LP, and the ever-increasing global urbanization makes LP one of the fastest-growing threats to our civilization. It is particularly dangerous because public awareness of its existence is exceptionally weak, as the presence of light is usually perceived as a good thing, generating safety and beauty, and it is difficult for people to understand that excess of light may turn against us. However, LP dysregulates the well-known circadian rhythms of humans and animals and disrupts normal plant physiology. Furthermore, in a light-polluted world, plant–pollinator relationships are also endangered, which can lead to disruptions in food chains. In this review, we will present various aspects of excessive lighting and propose solutions to mitigate the increasing LP, considering the threats it poses to all living organisms.

Pollutants doi: 10.3390/pollutants6010010

Authors: Yuichiro Osaka Atsuko Nishigaki

Reduced mud in the Yoro tidal flat (inner part of Tokyo Bay, Japan) consists of black and highly viscous sediment containing high levels of polycyclic aromatic hydrocarbons (PAHs). The mud is formed through the decomposition of terrestrial plants washed up on the tidal flat; however, the origin of PAHs within the mud has remained unclear. To investigate the origin of PAHs in the mud, we analyzed PAHs in the mud and fragments of terrestrial plants using gas chromatography–mass spectrometry. The total PAH concentrations except for perylene were comparable between the mud (336 ± 58 μg kg-dry−1) and the fragments of plants (247 ± 77–435 ± 235 μg kg-dry−1), and their compositional patterns were also similar. These results indicate that the high levels of PAHs in the mud primarily originated from the fragments of plants that composed the mud. Furthermore, the perylene (Pery) concentrations in the fragments of plants were the same as or higher than those in the mud, suggesting that the formation of Pery begins in the plant tissues even before the mud was formed. These findings reveal a previously unrecognized pathway by which terrestrial plants introduce PAHs into tidal flat environments.

Pollutants doi: 10.3390/pollutants6010009

Authors: Gabson Baguma Gadson Bamanya Hannington Twinomuhwezi Wycliffe Ampaire Ivan Byaruhanga Allan Gonzaga Ronald Ntuwa Wilber Waibale

Contamination of drinking water by potentially toxic elements (PTEs) remains a critical public-health concern in Uganda. This systematic review compiled and harmonized quantitative concentrations (mg/L) for key PTEs, lead (Pb), cadmium (Cd), arsenic (As), chromium (Cr), mercury (Hg), copper (Cu), zinc (Zn), nickel (Ni), cobalt (Co), manganese (Mn), and iron (Fe), across various potable and informal water sources used for drinking, including municipal tap water, boreholes, protected and unprotected springs, wells, rainwater, packaged drinking water, rivers, lakes, and wetlands. A comprehensive search of different databases and key institutional repositories yielded 715 records; after screening and eligibility assessment, 161 studies met the inclusion criteria, and were retained for final synthesis. Reported PTE concentrations frequently exceeded WHO and UNBS drinking water guidelines, with Pb up to 8.2 mg/L, Cd up to 1.4 mg/L, As up to 25.2 mg/L, Cr up to 148 mg/L, Fe up to 67.3 mg/L, and Mn up to 3.75 mg/L, particularly in high-risk zones such as Rwakaiha Wetland, Kasese mining affected catchments, and Kampala’s urban springs and drainage corridors. These hotspots are largely influenced by mining activities, industrial discharges, agricultural runoff, and corrosion of aging water distribution infrastructure, while natural geological conditions contribute to elevated background Fe and Mn in several regions. The review highlights associated health implications, including neurological damage, renal impairment, and cancer risks from chronic exposure, and identifies gaps in regulatory enforcement and routine monitoring. It concludes with practical recommendations, including stricter effluent control, expansion of low-cost adsorption and filtration options at household and community level, and targeted upgrades to water-treatment and distribution systems to promote safe-water access and support Uganda’s progress toward Sustainable Development Goal 6.

Pollutants doi: 10.3390/pollutants6010008

Authors: Oluseye Oludoye Charles C. Okolo Opeyemi Adebanjo-Aina Koleayo Omoyajowo Lanrewaju Ogunyebi

Unsafe disposal of pesticide waste remains a critical environmental and public health issue in developing agricultural systems. This study examined cocoa farmers’ disposal behaviours and their determinants across Nigeria’s major cocoa-producing regions using an explanatory sequential mixed-methods design. Quantitative data were collected from 391 farmers, followed by 23 in-depth interviews to contextualise behavioural drivers. Results showed that knowledge of pesticide risks and availability of disposal facilities significantly predicted safer disposal practices (R2 = 0.469, p < 0.05), whereas age had a negative influence. Qualitative findings revealed that negative attitudes, social norms, and limited infrastructure reinforced unsafe behaviours, while membership in farmers’ associations promoted safer practices through peer learning. A joint display demonstrated convergence between structural enablers (collection cages, extension support) and behavioural factors (knowledge, attitudes, norms). The study identifies a dual challenge of systemic shortcomings and behavioural inertia, suggesting that regulatory action alone is insufficient without farmer engagement and education. Policy and extension programmes should prioritise collection infrastructure, association-based training, and Integrated Pest Management to promote sustainable pesticide waste management. These insights advance understanding of pesticide disposal behaviour and offer actionable guidance for environmental governance in low- and middle-income agricultural contexts.

Pollutants doi: 10.3390/pollutants6010007

Authors: Aaron Bain Burton Gibson Brenique Lightbourne Kaitlyn Forbes Williamson Gustave

Eutrophication is a major threat to freshwater ecosystems, leading to harmful algal blooms, biodiversity loss, and hypoxia. Excessive nutrient loading, primarily from nitrates and phosphates, is driven by fertilizer runoff, sewage discharge, and agricultural practices. Sediment microbial fuel cells (sMFCs) have emerged as a potential bioremediation strategy for nutrient removal while generating electricity. Although various studies have explored ways to enhance sMFC performance, limited research has examined the relationship between external resistance, electricity generation, and nutrient removal efficiency. This study demonstrated effective nutrient removal from overlying water, with 1200 Ω achieving the highest nitrate and phosphate removal efficiency at 59.0% and 32.2%, respectively. The impact of external resistances (510 Ω and 1200 Ω) on sMFC performance was evaluated, with the 1200 Ω configuration generating a maximum voltage of 466.7 mV and the 510 Ω configuration generating a maximum current of 0.56 mA. These findings show that external resistance plays a major role in both electrochemical performance and nutrient-removal efficiency. Higher external resistance consistently resulted in greater voltage output and improved removal of nitrate and phosphate. The findings also indicate that sMFCs can serve as a dual-purpose technology for nutrient removal and electricity generation. The power output may be sufficient to support small, eco-friendly biosensing devices in remote aquatic environments while mitigating eutrophication.

Pollutants doi: 10.3390/pollutants6010006

Authors: Dirk Broßell Emilia Visileanu Catalin Grosu Asmus Meyer-Plath Maike Stange

Airborne micro- and nanoplastic particles (MNPs) are increasingly recognized as a potential occupational exposure hazard, yet substance-specific workplace data remain limited. This study quantified airborne MNP concentrations during polyester microfiber production using a correlative SEM–Raman approach that enabled chemical identification and size-resolved particle characterization. The aerosol mixture at the workplace was dominated by sub-micrometer particles, with PET—handled onsite—representing the main process-related MNP type, and black tire rubber (BTR) forming a substantial background contribution. Across both sampling periods, total MNP particle number concentrations ranged between 6.2 × 105 and 1.2 × 106 particles/m3, indicating consistently high particle counts. In contrast, estimated MNP-related mass concentrations were much lower, with PM10 levels of 12–15 µg/m3 and PM2.5 levels of 1.3–1.6 µg/m3, remaining well below applicable occupational exposure limits and near or below 8 h-equivalent WHO guideline values. Comparison with earlier workplace and indoor studies suggests that previously reported concentrations were likely underestimated due to sampling strategies with low efficiency for small particles. Moreover, real-time optical measurements substantially underestimated particle number and mass in this study, reflecting their limited suitability for aerosols dominated by small or dark particles. Overall, the data show that workplace MNP exposure at the investigated site is driven primarily by very small particles present in high numbers but low mass. The findings underscore the need for substance-specific, size-resolved analytical approaches to adequately assess airborne MNP exposure and to support future development of MNP-relevant occupational health guidelines.

Pollutants doi: 10.3390/pollutants6010005

Authors: Melissa I. Ortiz-Román Camila M. Martínez-Llaurador Claudia S. Jiménez-Velez Beatriz M. Purcell-Collazo Felix R. Román-Velázquez

Plastic pollution is a growing environmental crisis, with millions of tons of plastic entering the ocean each year and breaking down into microplastics and nanoplastics. These tiny particles pose a serious threat to marine life, particularly to zooplankton, which are essential to aquatic ecosystems. This study investigated the distribution and toxicity of polystyrene nanoplastics in Artemia salina (brine shrimp), a key model organism in ecotoxicology. Using specialized imaging and spectroscopy techniques, we tracked the presence of nanoplastics in A. salina and examined their effects on survival, behavior, and body structure. The results showed that nanoplastics accumulated in the gut and, at higher concentrations, caused gut deformities. The toxicity assay revealed that after 48 h of exposure, lethal concentrations decreased by nearly half compared with 24 h, demonstrating a time-dependent toxic effect. The estimated concentration that caused 50% mortality was 30.21 ± 6.44 mg/L. Additionally, these findings suggest that nanoplastics may impair the salt gland, affecting osmoregulation and energy allocation, leading to reduced feeding and pigmentation. These results highlight the potential risks of nanoplastics to marine organisms and emphasize the need for further research to understand their broader ecological and health impacts.

Pollutants doi: 10.3390/pollutants6010004

Authors: Seyyed Roohollah Masoomi Mohammadamin Ganji Andres Annuk Mohammad Eftekhari Aamir Mahmood Mohammad Gheibi Reza Moezzi

Harmful algal blooms (HABs) represent an escalating threat in marine and coastal ecosystems, posing increasing risks to ecological balance, public health, and blue economy industries including fisheries, aquaculture, and tourism. This review examines the impact of climate change and anthropogenic pressures on the escalation of HAB occurrences, focusing especially on vulnerable regions in Mexico, which are the primary case study for this investigation. The methodological framework integrates HAB risk assessment (RA) methods found in the literature. Progress in detection and monitoring technologies—such as sensing, in situ sensor networks, and prediction tools based on machine learning—are reviewed for their roles in enhancing early-warning systems and aiding decision support. The key findings emphasize four linked aspects: (i) patterns of HAB risk in coastal zones, (ii) deficiencies and prospects in HAB-related policy development, (iii) how governance structures facilitate or hinder effective actions, and (iv) the growing usefulness of online monitoring and evaluation tools for real-time environmental observation. The results emphasize the need for coupled technological and governance solutions to reduce HAB impacts, protect marine biodiversity, and enhance the resilience of coastal communities confronting increasingly frequent and severe bloom events.

Pollutants doi: 10.3390/pollutants6010003

Authors: Awnon Bhowmik Goutam Saha

Microplastics (MPs)—synthetic polymer particles less than 5 mm in size—have emerged as ubiquitous contaminants in terrestrial and aquatic environments worldwide, raising concerns about their ecological and human health impacts. While research has predominantly focused on urban and marine settings, evidence shows that rural ecosystems are also affected, challenging assumptions of pristine conditions outside cities and coasts. This review synthesizes current knowledge on the presence, pathways, and impacts of MPs in rural environments, highlighting complex contamination dynamics driven by both local sources (agricultural plastics, domestic waste, rural wastewater, and road runoff) and regional processes (atmospheric deposition, hydrological transport, and sediment transfer). Key findings highlight that rural lakes, streams, soils, and groundwater systems are active sinks and secondary sources of diverse MPs, predominantly polyethylene (PE), polypropylene (PP), and polyethylene terephthalate (PET) in fibrous and fragmented forms. These particles vary in size, density, and color, influencing their transport, persistence, and bioavailability. Ecological effects include bioaccumulation in freshwater species, soil degradation, and potential food chain transfer, while human exposure risks stem from contaminated groundwater, air, and locally produced food. Despite these growing threats, rural systems remain underrepresented in monitoring and policy frameworks. The article calls for context-specific mitigation strategies, enhanced wastewater treatment, rural waste management reforms, and integrated microplastics surveillance across environmental compartments.

Pollutants doi: 10.3390/pollutants6010002

Authors: Nehad F. Elshayeb Eqbal A. Sadoun Bothina M. Weheda Mohamed A. Shahba

This study examined the seasonal and spatial distribution of heavy metals (Cd, Pb, and Ni) in relation to environmental parameters in five regions of Greater Cairo, Egypt (Helwan, Al-Azhar, Al-Orman, Al-Orman Center, and Al-Moqattam) between 2023 and 2024 using Ficus nitida as a bioindicator. Leaf and soil samples were taken periodically and tested for heavy metal levels, growth factors, chlorophyll, NPK, and moisture content. Concentrations of Cd, Pb, and Ni were highest at Helwan, the industrial site, reaching 0.22 mg/kg, followed by Al-Azhar, a high-traffic urban area, with 0.12 mg/kg, particularly during the summer season. In contrast, the lowest concentrations (0.03 mg/kg) were recorded at Al-Orman Center and Al-Moqattam, both characterized as low-traffic residential zones. A positive correlation was observed between heavy metal concentrations in Ficus nitida leaves and those in the corresponding soils. Additionally, the minimum leaf area was recorded at Helwan during winter, followed by the Al-Azhar region, with values of 36.2 cm2 and 41.7 cm2, respectively. Reductions in chlorophyll content and nutritional composition were linked to heavy metal levels. Ficus nitida may function as a trustworthy bioindicator of the environmental heavy metal contamination and the health of urban ecosystems, and it accurately reflects soil and air pollution levels.

Pollutants doi: 10.3390/pollutants6010001

Authors: Marco Gola Stefano Capolongo Gaetano Settimo

Indoor Air Quality (IAQ) is a major public health concern, as prolonged exposure to indoor environments can significantly affect users’ well-being. In this context, the research proposes a sampling protocol, developed in compliance with ISO 16000 principles, for the assessment of key chemical and physical parameters influencing air quality in inpatient rooms. These spaces host fragile users, while also requiring adequate protection for healthcare staff. Referring to the scope of the paper, the study outlines a comprehensive methodology for monitoring selected volatile organic compounds (VOCs) and microclimatic factors—temperature and relative humidity—using passive samplers and/or active sensors. The protocol also integrates outdoor measurements to better understand the contribution of internal emission sources. Monitoring activities are scheduled over one year, with regular sampling campaigns (at least one week per month) to analyze seasonal variations and long-term trends. The flexible structure of the protocol allows it to be adapted to different research objectives and types of healthcare facilities. Overall, the proposed approach provides a replicable framework for assessing IAQ in healthcare settings and identifying the main factors affecting indoor environmental performance. This supports improvements in both environmental quality and health protection within healing spaces.

Pollutants doi: 10.3390/pollutants5040049

Authors: Konstantinos B. Simoglou Zisis Vryzas Emmanouil Roditakis

The study investigates Greek consumers’ beliefs and their assessment of the risks associated with consuming potatoes they perceive as contaminated with pesticide residues, aiming to understand the relationship between perceived risk and actual dietary exposure. A survey of 1318 participants was conducted, employing latent profile analysis to identify two distinct consumer profiles: Concerned Consumers, who prioritize certified products and exhibit lower potato consumption, and Confident Consumers, who demonstrate higher consumption levels and lower risk perception. Data from the consumer survey and the two-category grouping were benchmarked against data from the Greek report on pesticide residue monitoring in food to estimate exposure against established toxicological reference values. The results indicate that pesticide residues on potatoes in Greece remain significantly below established toxicological reference values, with mean exposures well within safety limits for both consumer groups. Despite the higher consumption among Confident Consumers, their exposure levels are still negligible. The findings highlight a disconnect between consumer perceptions of pesticide risk and actual exposure, suggesting that current agricultural practices are effective in safeguarding public health. This study underscores the importance of evidence-based risk communication to bridge the gap between consumer concerns and scientific reality, reinforcing the role of potatoes as a safe and essential food source.

Pollutants doi: 10.3390/pollutants5040048

Authors: Baljit Singh Abhijnan Bhat Gayathree Thenuwara Kamna Ravi Azza Silotry Naik Christine O’Connor Furong Tian

The general spread of water safety awareness and enforcement often masks the escalating risks of emerging contaminants (ECs) that evade standard detection and monitoring techniques. Traditional monitoring infrastructures depend heavily on localized laboratory-based testing, which is expensive, time-consuming, and reliant on specialized infrastructure and skilled personnel. While specific types of ECs and detection technologies have been examined in numerous studies, a significant gap remains in compiling and commenting on this information in a concise framework that incorporates global impact and monitoring strategies. We aimed to compile and highlight the impact ECs have on global water safety and how advanced sensor technologies, when integrated with digital tools such as the Internet of Things (IoT), artificial intelligence (AI), machine learning (ML), geographic information systems (GIS), and cloud-based analytics, can enhance real-time EC detection and monitoring. Recent case studies were reviewed for the assessment of EC types, global contamination, and current state-of-the-art for EC detection and their limitations. An emphasis has been placed on areas that remain unaddressed in the current literature: a cross-disciplinary integration of integrated sensor platforms, multidisciplinary research collaborations, strategic public–private partnerships, and regulatory bodies engagement will be essential in safeguarding public health, protecting aquatic ecosystems, and ensuring the quality and resilience of our water resources worldwide.

Pollutants doi: 10.3390/pollutants5040045

Authors: Anuli Njoku Mousa Al-Hassan Sharaban Tohura Kaleigh Albert Taryn Pierce Wendemi Sawadogo

There has been a decline in the age at which girls experience menarche worldwide. Research suggests that exposure to endocrine-disrupting chemicals is linked to negative health consequences, including early onset of menarche. This systematic review examined the association between exposure to endocrine-disrupting chemicals (EDCs) and the early onset of menarche. Comprehensive searches of the PubMed, Embase, Web of Science, and Scopus databases were conducted to find relevant studies published from inception to November 2024. Exposure to certain EDCs, such as particulate matter and phthalates, showed significant associations with earlier menarche onset, while exposure to other EDCs (e.g., pyrethroids) was linked to delayed menarche timing. Overall, there were mixed findings in the relationships between various EDC exposures and menarche onset. Few studies investigated how exposure to EDCs and early menarche differed by race and ethnicity. This underscores the need for more studies that examine the relationship between early menarche onset and exposure to endocrine-disrupting substances. Education and policy approaches are also warranted to address this issue.

Pollutants doi: 10.3390/pollutants5040047

Authors: Afia Ibnath Shimki Fahad Al Nur Sajid Zubaer Hosen

Rapid urbanisation and intensified poultry production have increased chicken feather waste (CFW), posing environmental concerns due to its recalcitrant keratin content. This study aimed to evaluate the potential of Actinomycetes, specifically Streptomyces sp., isolated from peat-rich soils, to degrade CFW and enhance nitrogen recovery. Chicken feathers collected from a slaughterhouse near Khulna University were washed, dried, ground, and inoculated with 2.5 mL of Streptomyces broth in a controlled composting setup. The decomposition process was monitored over eight days, with daily assessments of total and available nitrogen using the Micro-Kjeldahl method. The results demonstrated a significant increase (p ≤ 0.05) in nitrogen content in the Actinomycetes-treated decomposition group compared to the control. The highest total nitrogen content (6.43%) was observed on day 7, while peak available nitrogen (4.04%) occurred on day 8. The percentage of nitrogen recovery through Actinomycetes activity was 86.1%. These findings confirm the keratinolytic efficiency of Streptomyces in degrading feather waste and enhancing nitrogen mineralisation. Although nitrogen release was gradual, the resulting compost presents a viable slow-release organic fertiliser. This bioconversion approach offers an environmentally sustainable solution for poultry waste management and soil nutrient enrichment in agriculture.

Pollutants doi: 10.3390/pollutants5040046

Authors: Ahmed Abou-Shady Heba El-Araby

In the last 32 years (1993–2024), the application of electric fields in soil management (soil electrokinetic, SEK) has undergone several stages of optimization and intensification. SEK has used both alternating current (AC) and direct current (DC). Numerous fields, including agriculture, sedimentation, phosphorus management in soil and sludge, fertilizer production, consolidation, reclaiming salt-affected soils, metal extraction, dewatering, remediation of contaminated soil (both organic, such as PFAS, and inorganic, such as heavy metals), and soil nutrient availability, have utilized the SEK concept. Numerous innovations were included in the SEK equipment’s design or combined with other biological, chemical, and physical processes. While we recently published a review article on soil electrokinetic/electroosmosis–vacuum systems for sustainable soil improvement and contaminant separation, the current study illustrates the role of applying the pressure-assisted soil electrokinetics technique and shows the effect of the opposite technique. Four points were used to show the function of pressure-assisted soil electrokinetics based on our analysis of six search engines from 1993 to 2024 (the previous 32 years), including (1) polluted soil remediation, (2) dewatering, (3) soil improvement, and (4) making soil ready for electrokinetic action by applying pressure. In contrast to other intensification methods (such as reverse polarity, pulsed electric field, and design change), we found very few publications addressing pressure-assisted soil electrokinetics throughout the literature search. Most investigations focused on the dewatering mechanism, despite the paucity of relevant papers. In contrast to conventional electrokinetic remediation, pump-assisted electrokinetic-flushing remediation increased the removal efficiencies of Cs+ and Co2+ from contaminated soil by 2% and 6%, respectively. Additionally, the results demonstrated that the pressured electro-osmotic dewatering approach outperformed the conventional electrokinetic techniques. At 40 kPa, hydraulic conductivity was reduced four-fold by electro-rehabilitation for alternative fuels, while at 100 kPa, it was reduced three-fold. It was also observed that pressure may be used to achieve the soil ready for electrokinetic action in order to guarantee proper operation. Since there are not many articles on the subject, future research may examine how pressure-assisted soil electrokinetics can be integrated with vacuum systems, reverse polarity mode, pulsed electric field mode, modifying the SEK design, overcoming the formation of cracks, etc.

Pollutants doi: 10.3390/pollutants5040044

Authors: Kosuke Toshiki Kazumori Nishi

Kitchen waste management strongly affects greenhouse gas (GHG) emissions, especially in small municipalities with limited treatment options. This study assessed alternative strategies for Aya Town, Japan, by integrating life cycle assessment (LCA) with Geographical Information System (GIS)-based transport analysis. Six scenarios were designed, ranging from mandatory composting with frequent collection to full incineration at a regional waste-to-energy (WtE) facility. Emissions were estimated from transport, composting, and incineration processes, with sensitivity tests on composting electricity use (20, 50, and 90 kWh per ton) and WtE efficiency (15%, 17.9%, 20%, and 25%). The results showed that reducing collection frequency lowered emissions by about 9% relative to the current system, while decreasing composting participation further reduced emissions. Full incineration yielded the lowest emissions, whereas sensitivity analyses confirmed that facility parameters influenced absolute values but not the relative ranking of scenarios. These findings emphasize the importance of transport logistics, participation rates, and infrastructural context. High-quality compost may justify limited voluntary composting; however, WtE incineration remains the most robust option for climate mitigation in Japan’s incineration-based waste management system.

Pollutants doi: 10.3390/pollutants5040043

Authors: Mohammad Hasan Ahsan Habib Mohammad Alam Saiful Islam Ershad Halim

Poly- and perfluoroalkyl substances (PFASs) are persistent environmental pollutants widely used in industrial applications due to their thermal stability and chemical resistance. However, their persistence in the environment and potential health risks, including developmental and immunological issues, have raised significant concerns. This review highlights the industrial uses, environmental fate, and bioaccumulation of PFASs, emphasizing their widespread presence in air, water, soil, and biota. Major sources of PFAS contamination include industrial discharges, wastewater treatment, and military sites. The atmospheric transport of PFASs contributes to their deposition in remote ecosystems, while aquatic and soil contamination stems from both point and nonpoint sources. Bioaccumulation studies reveal that PFASs accumulate in organisms, leading to potential human exposure through food, water, and consumer products. This review calls for further research to address knowledge gaps in PFAS detection, behavior, and health impacts, while advocating for improved regulations to limit their release and exposure.

Pollutants doi: 10.3390/pollutants5040042

Authors: Tochukwu A. Ngwu Chinwe P. Oramah Komsoon Somprasong Chanapol Charoentanaworakun

Environmental Protection Plans (EPPs) are vital for mitigating the socio-ecological impacts of quarry operations, especially in emerging economies like Thailand, where rapid industrialization often intensifies air, water, noise, and land degradation. This study applies the social return on investment (SROI) framework to evaluate the cost-effectiveness of multi-domain EPPs implemented in a quarry. By applying compliance-based assessment and monetization of environmental and health co-benefits, annual economic outcomes were quantified for particulate matter (PM10), total dissolved solids (TDS), noise reduction, and carbon sequestration. The analysis revealed a high SROI ratio of 59.55:1, primarily driven by substantial health benefits from PM10 and noise abatement. This ratio also reflects consideration of investment from an annual operational cost, with a sensitivity analysis of incorporating an estimated capital expenditure, reducing the ratio to moderate value ranges of 5–10:1. A number of limitations, such as exclusion of capital costs, reliance on fixed proxies, and single-year scope, may overstate short-term returns, suggesting the application of stochastic methods for enhanced robustness. Overall, the findings demonstrate that EPPs deliver substantial economic and public health benefits, supporting their role in fostering community resilience and advancing sustainable operations in quarry sectors.

Pollutants doi: 10.3390/pollutants5040041

Authors: Mohammad Kazemi Garajeh Giovanni Laneve Hamid Rezaei Mostafa Sadeghnejad Neda Mohamadzadeh Behnam Salmani

For Sentinel-5P products, the European Space Agency (ESA) validates the data collected by the TROPOMI instrument onboard the Sentinel-5P satellite using a network of ground stations and various techniques such as ZSL-DOAS, Pandora, and MAXDOAS [...]

Pollutants doi: 10.3390/pollutants5040040

Authors: Almustafa Abd Elkader Ayek Abeer Hassan Al-Saleh

Monitoring air quality is crucial on a global level. However, it is important to acknowledge the limitations of satellite-derived data in measuring gas concentrations. The Sentinel-5 satellite estimates pollutant density within an atmospheric column by measuring both the reflected solar radiation and the emitted radiation from the top of the Earth’s atmosphere. In other words, it assesses the presence of pollutants within the atmospheric column, but it cannot generate a method to isolate the amount of pollutants near the Earth’s surface from the total measured by the satellite. The authors completely ignored the methodology for converting the pollutant’s gas density within the atmospheric column into parts per million. In this commentary, we aim to clarify that it is neither practically nor operationally feasible to perform what the authors claimed as an evaluation of the accuracy of Sentinel-5p measurements from the ground stations they mentioned.

Pollutants doi: 10.3390/pollutants5040039

Authors: Jaime Carbajo Jefferson E. Silveira Inês Gomes Annabel Fernandes Lurdes Ciríaco Alicia L. García-Costa Juan A. Zazo Jose A. Casas

Cyanuric acid (CYA) is widely used as a chlorine stabilizer in swimming pools, but concentrations above 75 mg L−1 cause overstabilization and loss of disinfection capacity. This study evaluated CYA removal by advanced oxidation processes, including heterogeneous photocatalysis, photo-Fenton, photo-persulfate, and anodic oxidation (AO). AO with boron-doped diamond anodes proved most effective, achieving up to 90% total organic carbon removal in ultrapure water. When applied to real swimming pool samples (118 and 251 mg L−1 CYA), the process achieved significant CYA abatement, demonstrating its potential as a practical strategy to control overstabilization without additional chemicals.

Pollutants doi: 10.3390/pollutants5040038

Authors: Georges K. Kome Caroline A. Kundu Michael A. Okon Roger K. Enang Samuel A. Mesele Julius Opio Eric Asamoah Chrow Khurshid

There is an urgent need for an updated and relevant soil information system (SIS) to sustainably use and manage the land across Africa. Accurate data on soil pollution is essential for effective decision-making in soil health monitoring and management. Unfortunately, the data and information are not usually presented in formats that can easily guide decision-making. The objectives of this work were to (i) assess the availability of soil pollution maps, (ii) evaluate the methodologies used in creating these maps, (iii) explore the role of soil pollution maps in soil health monitoring, and (iv) identify gaps and challenges in soil pollution mapping in Africa. Soil pollution maps across Africa are created on a local scale, with highly variable sampling size and low sampling density. The most used mapping techniques include spatial interpolation (kriging and inverse distance weighting). Among the types of soil pollutants mapped, heavy metals have received priority, while pesticides and persistent organic pollutants have received less attention. Soil pollution mapping is not incorporated within the SIS framework due to lack of reliable spatially comprehensive data and technological and institutional barriers. Current efforts remain fragmented, site-specific, and methodologically inconsistent, resulting in significant data gaps that hinder reliable monitoring and limit progress in soil pollution mapping.

Pollutants doi: 10.3390/pollutants5040037

Authors: Swati Srivastava Dheeraj Raya Rajni Sharma Shiv Kumar Giri Kanu Priya Anil Kumar Gulab Singh Saurabh Sudha Dhiman

The alarming increase in the use of chemically driven pesticides for enhanced crop productivity has severely affected soil fertility, ecosystem balance, and consumer health. Inadequate handling protocols and ineffective remediation strategies have led to elevated pesticide concentrations, contributing to human respiratory and metabolic disorders in humans. In the current context, where agricultural activities and pesticide applications are intertwined, strong and sustainable remediation strategies are essential for environmental protection without sacrificing crop productivity. Various bio-inspired methods have been reported, such as phytoremediation, bioremediation, and in situ remediation; however, limited success has been observed with either single or combined approaches. Consequently, biopolymer biomanufacturing, nanoparticle-based bioengineering, and computational biology for improved understanding of mechanisms have been revisited to incorporate updated methodologies that detail the fate and action of harmful chemical pesticides in agriculture. An in silico mechanistic approach has been emphasized to understand the molecular mechanisms involved in agricultural pesticides’ degradation using nanomaterials. A roadmap has been created by integrating cutting-edge machine learning techniques to develop nature-inspired sustainable agricultural practices and contaminant disposal methods. This review represents a pioneering effort to explore the roles of wet-lab chemistry and in silico methods in mitigating the effects of agricultural pesticides, providing a comprehensive strategy for balancing environmental sustainability and agricultural practices.

Pollutants doi: 10.3390/pollutants5040036

Authors: Tong-Bou Chang Jhong-Wei Huang

When driving at highway speeds, the airtightness and ventilation mode of the cabin can significantly affect the in-cabin air quality. Accordingly, this study conducted on-road driving experiments along four highways in Tainan City, Taiwan, to examine the effects of different ventilation strategies and driving speeds on the concentrations of three pollutants (carbon dioxide (CO2), PM2.5, and PM10) in the cabin of a mid-size sedan. During the test, the vehicle will travel at a constant speed of 60, 70, 80, 90, 100, 110 and 120 km/h depending on the traffic conditions. When driving on the system interchanges, the vehicle speed was maintained at 40 and 50 km/h. Ventilation strategies are divided into fresh air mode and recirculation air mode. The results revealed that leakage ventilation at high speeds allowed more outdoor air to infiltrate the cabin. This reduced the CO2 concentration but slightly increased the particulate matter (PM) when the ventilation system was operated in the recirculation mode. The continuous use of the recirculation air mode for extended periods resulted in a potentially hazardous increase in the CO2 concentration. Thus, periodic switching to the fresh air mode is recommended to ensure that the in-cabin CO2 concentration remains below the ASHRAE threshold of 1000 ppm. In the fresh air mode, the PM2.5 and PM10 concentrations decreased as the vehicle speed increased. In the recirculation mode, the cabin filters maintained lower in-cabin PM levels than in the fresh-air mode. The experimental data were fitted using a curve-fitting technique to quantify the relationships between the vehicle speed and the in-cabin CO2, PM2.5, and PM10 concentrations under the two ventilation strategies. The findings of this study provide useful practical guidelines for optimizing the vehicle ventilation strategy to improve the in-cabin air quality and enhance occupant health and safety during highway driving.

Pollutants doi: 10.3390/pollutants5040035

Authors: Dafydd Phillips

South Korea faces high levels of air pollution and is currently not on track to meet its transport sector 2030 and 2050 greenhouse gas emission reduction targets primarily due to infrastructural limitations. This study examines the potential health benefits of a more rapid green transition of South Korea’s transport sector from 2026 to 2050 in terms of avoided premature deaths and years of life lost due to reduced ambient PM2.5 exposure. The research conducts a scenario analysis comparing the business-as-usual trajectory of the transport sector with two alternative scenarios. In the first alternative scenario, South Korea’s transport sector achieves its 2030 NDC in 2035 and carbon neutrality in 2050 with a reliance on CCUS for emission capture. The second alternative scenario entails stronger climate action in which the transport sector meets the 2030 NDC target in 2030 and the 2050 carbon neutrality transport sector target through a complete green transition to electric vehicles and hydrogen vehicles. The first alternative scenario results in an average of 80 avoided premature deaths (775 avoided years of life lost) and 53 MTCO2e avoided emissions per year from 2026 to 2050. The second more rapid green transition scenario of South Korea’s transport sector achieves an average of 96 avoided premature deaths (925 avoided years of life lost) and 66 MTCO2e avoided emissions per year. This research supports a more rapid green transition of South Korea’s transport sector for both health and climate gains.

Pollutants doi: 10.3390/pollutants5040034

Authors: Gareth David Walsh Tamaryn Menneer Richard Alan Sharpe

Introduction: Increased exposure to air pollution poses a burden to society and healthcare systems worldwide, with increased risk of morbidity and mortality. Indoor concentrations of air pollutants, such as particulate matter, are a public health concern because they can be present in higher concentrations than outside. Unlike the effects of indoor environmental tobacco smoke (ETS), there is a dearth of research that includes the impact of e-cigarettes on particulate matter concentrations in the home, which is the focus of this study. Method: Participant, household, and sensor information were obtained from 164 lower-income households located in Cornwall, South West of England. Daily sensor readings were obtained for PM2.5 for one year. Descriptive statistics were used to describe study participant characteristics and health status. Mean indoor averages, median PM2.5 measurements, and two-tailed tests were used to assess differences in concentrations of PM2.5. Results: The 164 surveyed households included 315 residents (67% female) with a mean adult age of 57 (22–92). Half of all homes were in the 10% most deprived neighbourhoods in England. Thirty-four per cent of participants were current smokers, and of these 36% have asthma and had seen a doctor in the last year (cf. never smokers 14%, ex-smokers 25%). Mean annual PM2.5 was highest in smoking households (14.07 µg/m3) and smoking and vaping households (9.18 µg/m3), and lower in exclusive vaping households (2.00 µg/m3) and smoke and vape-free households (1.28 µg/m3). Monthly levels of PM2.5 fluctuated seasonally for all groups, with the highest recordings in winter and the lowest in summer. Discussion and Conclusion: In this preliminary study, we conducted secondary data analyses using monitoring data from a large health and housing study to assess factors leading to elevated indoor concentrations of particulate matter. Indoor concentrations appeared to be highest in homes where residents smoked indoors. The use of e-cigarettes in the home also appeared to modify concentrations of particulate matter, but levels were lower than in homes with tobacco smoke. We were not able to determine the relationship between smoking and/or vaping indoors and particulate matter, which supports the need for studies of larger sample sizes and more complex longitudinal monitoring. This will help assess the timing and extent of exposures resulting from smoking and vaping indoors, along with a range of other chemical and biological exposures and their corresponding health effects.

Pollutants doi: 10.3390/pollutants5040033

Authors: Milena Kercheva Patrycja Boguta Kamil Skic Viktor Kolchakov Katerina Doneva Maya Benkova

Soil contamination with heavy metals (HM) poses a risk to human health and can impact different soil functions. This study aimed to determine the influence of heavy metal pollution on the physical and physicochemical characteristics of the two profiles of alluvial–deluvial soil under grassland located at different distances from the Aurubis-Pirdop Copper smelter in Bulgaria. Data for soil particle-size distribution, soil bulk and particle densities, mineralogical composition, soil organic carbon contents, cation exchange properties, surface charge, soil water retention curves, pore size distribution—obtained by mercury intrusion porosimetry (MIP)—and thermal properties were obtained. The contents of Pb, Cu, As, Zn, and Cd were above the maximum permissible level in the humic horizon and decreased with depth and distance from the Copper smelter. Depending on HM speciation, the correlations are established with SOC and most physicochemical parameters. It can be concluded that the HMs impact the clay content, specific surface area, distribution of pores, and the water stability of soil aggregate fraction 1–3 mm to varying degrees.

Pollutants doi: 10.3390/pollutants5040032

Authors: Amber Hatter Daniel P. Heintzelman Megan Heminghaus Jonathan Foglein Mahbubur Meenar Eli K. Moore

Increased precipitation and extreme weather due to climate change can remobilize recent and legacy environmental contaminants from soil, sediment, and sewage overflows. Heavy metals are naturally distributed in Earth’s crust, but anthropogenic activity has resulted in concentrated emissions of toxic heavy metals and deposition in surrounding communities. Cities around the world are burdened with heavy metal pollution from past and present industrial activity. The city of Camden, NJ, represents a valuable case study of climate impacts on heavy metal mobilization in stormwater runoff due to similar legacy and present-day industrial pollution that has taken place in Camden and in many other cities. Various studies have shown that lead (Pb) and other toxic heavy metals have been emitted in Camden due to historic and recent industrial activity, and deposited in nearby soils and on impervious surfaces. However, it is not known if these heavy metals can be mobilized in urban stormwater, particularly after periods of high precipitation. In this study, Camden, NJ stormwater was collected from streets and parks after heavy rain events in the winter and spring for analysis with inductively coupled plasma-mass spectrometry (ICP-MS) to identify lead (Pb), mercury (Hg), cadmium (Cd), and arsenic (As). Lead was by far the most abundant of the four target elements in stormwater samples followed by Hg, Cd, and As. The locations with the highest Pb concentrations, up to 686.5 ppb, were flooded allies and streets between commercial and residential areas. The highest concentrations of Hg (up to 11.53 ppb, orders of magnitude lower than Pb) were found in partially flooded streets and ditches. Lead stormwater concentrations exceed EPA safe drinking levels at the majority of analyzed locations, and Hg stormwater concentrations exceed EPA safe drinking levels at all analyzed locations. While stormwater is not generally ingested, dermal contact and hand-to-mouth behavior by children are potential routes of exposure. Heavy metal concentrations were lower in stormwater collected from parks and restored areas of Camden, indicating that these areas have a lower heavy metal exposure risk. This study shows that heavy metal pollution can be mobilized in stormwater runoff, resulting in elevated exposure risk in industrial cities.

Pollutants doi: 10.3390/pollutants5030031

Authors: Mayuko Yagishita Shogo Sakita Satoshi Nakai Kazuyuki Nishimura Wataru Nishijima

The aim of this study was to devise a methodology for the on-site evaluation of the potential presence of persistent organic pollutants (POPs) in incoming waste materials. A novel approach to POP screening was developed, integrating an excitation–emission matrix method, which facilitates facile and comprehensive measurement, with machine learning of the resulting spectral images. With this approach, it is possible to determine the presence or absence of POPs with very high accuracy for screening, with a correct response rate of ≥75% and a specificity ≥80%. Assuming that this method is applied to actual delivery, we estimate that it is possible to obtain a discrimination result in about 10 min after sample removal.

Pollutants doi: 10.3390/pollutants5030030

Authors: Pedro Almeida Joana Antunes Filipe Pedra Rita Ventura Corina Carranca

Plastics have been widely used in agriculture, particularly as mulching materials, due to their ability to improve soil conditions and enhance productivity. However, their degradation into microplastics (MPs) raises significant environmental and agronomic concerns, as these particles may change soil properties, affect microbial communities, and pose risks to surrounding ecosystems. While methodologies for MP detection in aquatic environments are well established, the analysis of MPs in soils remains challenging due to the complexity and heterogeneity of soil matrices. Currently, there is no standardized protocol for the determination of MPs in soils. This study critically evaluated and compared three different pre-treatment methods for removing organic matter from soil prior to MP analysis in an agricultural soil, and proposes a comprehensive methodology comprising two main phases: (i) organic matter removal, a crucial step of MP particles, and (ii) density separation of MP particles. Three distinct removal chemical methods were tested using samples from an agricultural soil in Southern Portugal. The most effective method was then applied to assess MP particles in an experimental field, using soil samples collected before mulching and 14 months later beneath a polyethylene-based soil cover. This was one of the first studies contributing to the establishment of a routine methodology for monitoring MPs in soils, particularly the agricultural soils, ensuring compliance with the future “Directive for Soil Monitoring”.

Pollutants doi: 10.3390/pollutants5030029

Authors: Maria Renata S. Souto Adriana M. Pimenta Rita I. L. Catarino Maria Fernanda C. Leal Eugénia T. R. Simões

Milk and dairy products play a key role in the human diet but may also be vehicles for toxic contaminants, particularly heavy metals and metalloids (HMs), such as lead (Pb), cadmium (Cd), mercury (Hg), and arsenic (As). This integrative review examines peer-reviewed studies published between 2015 and 2025 to examine sources, occurrence, and health risks associated with HM contamination in milk and dairy products. Key sources include industrial emissions, agricultural runoff, contaminated feed and water, and inadequate packaging. This review highlights regulatory inconsistencies, limited surveillance, and underuse of metal speciation analysis, which hinder accurate toxicity assessment. Advances in trace-level HM detection systems are discussed in terms of sensitivity, accessibility, and feasibility. Studies from diverse geographic regions frequently report high levels of Pb and Cd in samples originating from industrialized areas in low- and middle-income countries. Health risk indicators, such as target hazard quotients (THQs) and margins of exposure (MOEs), often exceed safety thresholds, particularly in children, indicating significant public health risks, especially with prolonged exposure. These findings underscore the urgent need for systematic contaminant monitoring, harmonized regulations, source-focused mitigation policies, and investment in rapid, cost-effective testing technologies to safeguard milk and dairy product safety worldwide.

Pollutants doi: 10.3390/pollutants5030028

Authors: Mallory J. Llewellyn Muhammad S. Siddique Emma Ivantsova Bradford W. Daigneault Tracie R. Baker Christopher J. Martyniuk

Lead (Pb) is a naturally occurring metal that is environmentally ubiquitous due to industrial activities, such as mining, smelting, and fossil fuel combustion. Exposure to Pb adversely affects the central nervous system, gastrointestinal tract, lungs, liver, bones, and cardiovascular system, leading to a multitude of negative health impacts, such as anemia and neurological disorders. While significant research has focused on the effects of Pb on the nervous and immune systems, Pb’s impact as a reproductive endocrine disruptor remains largely understudied. The first objective of this review was to collate the current literature regarding the effects of Pb on the reproductive system of aquatic species (primarily fish) and agricultural livestock to highlight the ecological significance and impacts on animal health. Literature supports the hypothesis that exposure to Pb can impede reproductive processes by affecting hormone levels, reproductive organ development, and fertility. A second objective of this review was to elucidate putative mechanisms underlying Pb as a reproductive endocrine disruptor using molecular data and computational approaches. Based on transcriptomics data, Pb is hypothesized to perturb key pathways important for hypothalamic–pituitary–gonadal axis functions, such as circadian regulation and estrogen receptor signaling. Given the widespread environmental presence of Pb, understanding these mechanisms is essential for improving risk assessments and protecting animal reproductive health.

Pollutants doi: 10.3390/pollutants5030027

Authors: Helena Cristina Vasconcelos Ana Catarina Ferreira Maria Gabriela Meirelles

This study investigated the extent to which the North Atlantic Oscillation (NAO) modulated daily surface-level concentrations of ozone (O3), nitrogen dioxide (NO2), and sulfur dioxide (SO2) on São Miguel Island, Azores, between 2017 and 2021. Using validated data from two air quality monitoring stations, São Gonçalo (SG) (urban background) and Ribeira Grande (RG) (semi-urban), we applied descriptive statistics, seasonal Pearson correlations, and robust linear regression models to assess pollutant responses to NAO variability. The results reveal a significant and positive association between NAO phases and O3 concentrations, particularly in spring and summer. NO2 levels exhibited a strong negative correlation with NAO during summer in urban settings, indicating enhanced atmospheric dispersion. In contrast, SO2 concentrations showed weak and inconsistent relationships with the NAO index, likely reflecting the influence of local and episodic sources. These findings demonstrate that large-scale synoptic drivers such as the NAO can significantly modulate pollutant dynamics in island environments and should be integrated into air quality forecasting and environmental health planning strategies in small island territories.

Pollutants doi: 10.3390/pollutants5030026

Authors: Tasha Siame Yisa Adeniyi Abolade Famodu Omotayo Albert Junior Nyarko Mu’awiya Baba Aminu Uchechukwu Anthony Ogwurumba Bertha Onyenachi Akagbue Fatima Abdulmalik Hareyani Zabidi

Exposure to potentially toxic elements (PTEs) in commonly used substances remains a serious public health concern, especially in low-regulation environments. This study assessed and compared the concentrations of five PTEs, cadmium (Cd), lead (Pb), zinc (Zn), iron (Fe), and copper (Cu), in marijuana and Aspen-brand cigarettes consumed in Bauchi, Nigeria. Using atomic absorption spectrophotometry (AAS), we analyzed PTE content in both substances after acid digestion and proper calibration. Cigarettes showed higher levels of all tested metals. Cd (3.12 μg/g) and Pb (0.88 μg/g) in cigarettes exceeded WHO limits, while marijuana contained lower levels of Cd (0.645 μg/g) and Pb (0.11 μg/g), with only Cd approaching the level that poses environmental and public health concern. Zn (71.2 μg/g), Cu (64.0 μg/g), and Fe (19.2 μg/g) were also significantly higher in cigarettes (p < 0.01). The high levels of Cd and Pb in cigarettes indicate that smokers are more exposed to harmful PTEs through inhalation than marijuana users, which points to a greater health risk from cigarette use. These findings call for stronger policies and regulations that ensure cleaner agricultural practices and industrial accountability to minimize exposure to harmful PTEs and protect community health in Bauchi.

Pollutants doi: 10.3390/pollutants5030025

Authors: Artemisia Kokkinari Evangelia Antoniou Kleanthi Gourounti Maria Dagla Aikaterini Lykeridou Stefanos Zervoudis Eirini Tomara Georgios Iatrakis

(1) Background: Dioxins and dioxin-like polychlorinated biphenyls (dl-PCBs) are persistent organic pollutants (POPs), characterized by high toxicity and strong lipophilicity, which promote their bioaccumulation in human tissues. Their detection in breast milk raises concerns about early-life exposure during lactation. Although dietary intake is the primary route of maternal exposure, environmental pathways—including inhalation, dermal absorption, and residential proximity to contaminated sites—may also significantly contribute to the maternal body burden. (2) Methods: This narrative review examined peer-reviewed studies investigating maternal and environmental determinants of dioxin and dl-PCB concentrations in human breast milk. A comprehensive literature search was conducted in PubMed, Scopus, and Web of Science (2000–2024), identifying a total of 325 records. Following eligibility screening and full-text assessment, 20 studies met the inclusion criteria. (3) Results: The included studies consistently identified key exposure determinants, such as high consumption of animal-based foods (e.g., meat, fish, dairy), living near industrial facilities or waste sites, and maternal characteristics including age, parity, and body mass index (BMI). Substantial geographic variability was observed, with higher concentrations reported in regions affected by industrial activity, military pollution, or inadequate waste management. One longitudinal study from Japan demonstrated a declining trend in dioxin levels in breast milk, suggesting the potential effectiveness of regulatory interventions. (4) Conclusions: These findings highlight that maternal exposure to dioxins is influenced by identifiable environmental and behavioral factors, which can be mitigated through public health policies, targeted dietary guidance, and environmental remediation. Breast milk remains a critical bioindicator of human exposure. Harmonized, long-term research is needed to clarify health implications and minimize contaminant transfer to infants, particularly among vulnerable populations.

Pollutants doi: 10.3390/pollutants5030024

Authors: Enno Merivee Anne Mürk Karin Nurme Mati Koppel Angela Ploomi Marika Mänd

Environmental risk assessment (ERA) for pesticide approval in the context of predatory insects remains inadequate as it often overlooks the influence of agricultural practices. An increasing number of studies have shown that prolonged and synergistic pesticide exposure can elevate insect mortality. However, such effects remain largely unstudied in non-target predatory carabid beetles. The carabid beetle Platynus assimilis was subjected to repeated oral and continuous contact exposure to low doses of prothioconazole (20 g·ha−1), lambda-cyhalothrin (0.4 g·ha−1), or their combination over a 64-day period. The food consumption rate, body mass, locomotor activity, and mortality were monitored throughout the experiment. All pesticide-treated groups showed significantly increased final mortality, with median lethal times (LT50) of 51.6 days for prothioconazole, 60.3 days for lambda-cyhalothrin, and 12.2 days for their combination. A significant synergistic effect on mortality was observed in the combined treatment group, with the highest synergistic ratio detected 20 days after the first exposure. Pesticide-treated beetles exhibited significant abnormalities in locomotor activity and body mass compared to the untreated group. These findings demonstrate that both time-cumulative mortality and potential synergistic interactions, reflecting field-realistic conditions, must be considered in ERA. Failure to do so may lead to an underestimation of pesticide toxicity to predatory carabids.

Pollutants doi: 10.3390/pollutants5030023

Authors: Walid Ben Ameur Ali Annabi Kaddachi Rania Mauro Marini

Seafood contamination by heavy metals is a growing public health concern, particularly in regions like Tunisia where seafood is a major dietary component. This study assessed concentrations of cadmium (Cd), copper (Cu), lead (Pb), and zinc (Zn) in the muscle tissue of the red shrimp Parapenaeus longirostris, collected in 2023 from four coastal regions: Bizerte, Monastir, Kerkennah, and Gabes. Metal analysis was conducted using flame atomic absorption spectroscopy. This species was chosen due to its ecological and economic importance. The study sites were chosen based on their differing levels of industrial, urban, and agricultural influence, providing a representative overview of regional contamination patterns. Mean concentrations were 1.04 µg/g for Zn, 0.59 µg/g for Cu, 1.56 µg/g for Pb, and 0.21 µg/g for Cd (dry weight). Pb was the most prevalent metal across sites. Statistically significant variation was observed only for Cu (p = 0.0334). All metal concentrations were below international safety limits set by FAO/WHO and the European Union. Compared to similar studies, the levels reported were similar or slightly lower. Human health risk was evaluated using target hazard quotient (THQ), hazard index (HI), and cancer risk (CR) values. For adults, THQ ranged from 5.44 × 10−6 to 8.43 × 10−4, while for children it ranged from 2.40 × 10−5 to 3.72 × 10−3. HI values were also well below 1, indicating negligible non-carcinogenic risk. CR values for Cd and Pb in both adults and children fell within the acceptable risk range (10−6 to <10−4), suggesting no significant carcinogenic concern. This study provides the first field-based dataset on metal contamination in P. longirostris from Tunisia, contributing valuable insights for seafood safety monitoring and public health protection.

Pollutants doi: 10.3390/pollutants5030022

Authors: George F. Antonious Anjan Nepal Basanta Neupane

The application of animal manure and organic soil amendments as an alternative to expensive inorganic fertilizers is becoming more prevalent in the USA and worldwide. A field experiment was conducted on Bluegrass–Maury silty loam soil at the Kentucky State University Research Farm using the Kennebec variety of white potato (Solanum tuberosum) under Kentucky climatic conditions. The study involved 12 soil treatments in a randomized complete block design. The treatments included four types of animal manures (cow manure, chicken manure, vermicompost, and sewage sludge), biochar at three application rates (5%, 10%, and 20%), and native soil as control plots. Additionally, animal manures were supplemented with 10% biochar to assess the influence of combining biochar with animal manure on the accumulation of heavy metals in potato tubers. The study aimed to (1) determine the concentration of seven heavy metals (Cd, Cr, Ni, Pb, Mn, Zn, Cu) and two essential nutrients (K and Mg) in soils treated with biochar and animal manure, and (2) assess metal mobility from soil to potato tubers at harvest by determining the bioaccumulation factor (BAF). The results revealed that Cd, Pb, Ni, Cr, and Mn concentrations in potato tubers exceeded the FAO/WHO allowable limits. Whereas the BAF values varied among the soil treatments, with Cd, Cu, and Zn having high BAF values (>1), and Pb, Ni, Cr, and Mn having low BAF values (<1). This observation demonstrates that potato tubers can remediate Cd, Cu, and Zn when grown under the soil amended with biochar and animal manure.

Pollutants doi: 10.3390/pollutants5030021

Authors: Opeyemi Adebanjo-Aina Oluseye Oludoye

Agriculture relies on the widespread application of nitrogen fertilisers to improve crop yields and meet the demands of a growing population. However, the excessive use of these fertilisers has led to significant water quality challenges, posing risks to aquatic life, ecosystems, and human health. This study examines the relationship between synthetic nitrogen fertiliser usage and water pollution while identifying gaps in existing research to guide future studies. A systematic search across databases (Scopus, Web of Science, and Greenfile) identified 18 studies with quantitative data, synthesised using a single-group meta-analysis of means. As the data were continuous, the mean was used as the effect measure, and a random-effects model was applied due to varied study populations, with missing data estimated through statistical assumptions. The meta-analysis found an average nitrate concentration of 34.283 mg/L (95% confidence interval: 29.290–39.276), demonstrating the significant impact of nitrogen fertilisers on water quality. While this average remains marginally below the thresholds set by the World Health Organization (50 mg/L NO3−) and EU Nitrate Directive, it exceeds the United States Environmental Protection Agency limit (44.3 mg/L NO3−), signalling potential health risks, especially in vulnerable or unregulated regions. The high observed heterogeneity (I2 = 100%) suggests that factors such as soil type, agricultural practices, application rate, and environmental conditions influence nitrate levels. While agriculture is a key contributor, other anthropogenic activities may also affect nitrate concentrations. Future research should comprehensively assess all influencing factors to determine the precise impact of nitrogen fertilisers on water quality.

Pollutants doi: 10.3390/pollutants5030020

Authors: Shila Kandel Naja’Ree Campbell Abubakar Abdulkadir Kristin Moore Raphyel Rosby Ekhtear Hossain

4-Aminodiphenylamine (4-ADPA) is a common additive in rubber tires, known for its antioxidant properties. It plays a crucial role in enhancing tire durability by preventing issues such as drying, cracking, and degradation from prolonged exposure to environmental factors like heat, oxygen, and ozone. However, despite its advantages in extending tire lifespan, the use of 4-ADPA raises significant environmental concerns. As tires wear down, microscopic tire wear particles (TWPs) containing 4-ADPA are released into the environment with substantial leaching, contaminating the waterways. The 4-ADPA leachates pollute and pose a threat to aquatic ecosystems, affecting various forms of marine life. The current study investigates the ecotoxicological effects of 4-ADPA on the aquatic plant Lemna minor (L. minor), focusing on its impact on relative growth and physiological biomarkers. Several parameters were assessed to evaluate ecotoxicity, including frond morphology, fresh biomass, total frond number, chlorophyll content, and starch accumulation. L. minor was grown for 7 and 14 days under controlled laboratory conditions using Hoagland media with varying concentrations of 4-ADPA (10–100 μg/L), while a control group was maintained in media without 4-ADPA. The results indicate that exposure to 4-ADPA led to a dose-dependent reduction in fresh biomass, total frond number, and chlorophyll levels. Lugol’s staining revealed increased starch accumulation in the fronds after exposure to 4-ADPA. The biological effects observed in L. minor following exposure to 4-ADPA, even at environmentally relevant concentrations, demonstrate a significant ecotoxicological impact on aquatic ecosystems. Further research involving additional species and investigating the mechanisms behind 4-ADPA toxicity is recommended to better understand its long-term consequences.

Pollutants doi: 10.3390/pollutants5030019

Authors: Natalija Špeh Anja Bubik

Karst aquifer systems are highly vulnerable due to their unique underground water flow characteristics, making them prone to contamination and abandonment. This study compares an active karst water source (Ljubija) with a previously abandoned one (Rečica) to assess freshwater quality and water protection risks, especially as water scarcity becomes a concern during dry summer periods. The Ljubija and Rečica catchments, designated as water protection areas (WPAs), were monitored over a year (January–December 2020). Groundwater (GW) and surface water (SW) were analyzed twice a month during both dry and wet periods, adhering to European and national guidelines. An interdisciplinary approach integrated natural and human impact indicators, linking water quality to precipitation, hydrogeography, and landscape characteristics. After Slovene regulation standards (50 mg/L), the Ljubija source demonstrated stable water quality, with low nitrate levels (average 2.6 mg/L) and minimal human impact. In contrast, the Rečica catchment was more vulnerable, with its GW excluded from drinking use since the 1990s due to organic contamination, worsened by the area’s karst hydrogeology. In 2020, its nitrate concentration averaged 6.0 mg/L. These findings highlight the need for improved monitoring regulations, particularly for vulnerable karst water sources, to safeguard water quality and ensure sustainable use.

Pollutants doi: 10.3390/pollutants5030018

Authors: Joel Henrique Ellwanger Marina Ziliotto José Artur Bogo Chies

The metalloid arsenic (As) and the metals lead (Pb) and mercury (Hg), which together we call the “Toxic Triad”, are among the pollutants of greatest global concern, harming the health of millions of people and contributing to biodiversity loss. The widespread distribution of As, Pb and Hg facilitates the exposure of humans and other species to these elements simultaneously, potentially amplifying their individual toxic effects. While As, Pb and Hg are well established as toxic elements, the mechanisms by which they interact with genetic material and impact the health of various species remain incompletely understood. This is particularly true regarding the combined effects of these three elements. In this context, the objective of this work was to perform a toxicogenomic analysis of As, Pb and Hg to highlight multiple aspects of element-gene interactions, in addition to revisiting information on the genotoxicity and carcinogenicity of the Toxic Triad. By using The Comparative Toxicogenomics Database, it was possible to identify that As interacts with 7666 genes across various species, while Pb influences 3525 genes, and Hg affects 692 genes. Removing duplicate gene names, the three elements interact with 9763 genes across multiple species. Considering the top-20 As/Pb/Hg-interacting genes, catalase (CAT), NFE2 like bZIP transcription factor 2 (NFE2L2), caspase 3 (CASP3), heme oxygenase (HMOX1), tumor necrosis factor (TNF), NAD(P)H quinone dehydrogenase 1 (NQO1) and interleukin 6 (IL6) were the most frequently observed. In total, 172 genes have the potential to interact with the three elements. Gene ontology analysis based on those genes evidenced that the Toxic Triad affects several cellular compartments and molecular functions, highlighting its effect on stimulation of toxic stress mechanisms. These 172 genes are also associated with various diseases, especially those of the urogenital tract, as well as being related to biological pathways involved in infectious diseases caused by viruses, bacteria and parasites. Arsenic was the element with the best-substantiated genotoxic and carcinogenic activity. This article details, through a toxicogenomic approach, the genetic bases that underlie the toxic effects of As, Pb and Hg.

Pollutants doi: 10.3390/pollutants5030017

Authors: Andrew S. Mitchell Mark Lemon Gillian H. Drew

Air quality management concerns the assessment, analysis and mitigation strategies associated with ensuring that air is breathable and non-toxic. Successful management is a cognitively intensive task, knowledge-focused and converges multiple sources of information to develop a shared understanding of a problem. To operate effectively in this space, managers and operational teams share common points of reference in discussing problems and solutions, strategies, tactical briefings, etc., and communication and technical language use are key to the discipline. However, few studies have homed in on the language communities of air quality management discourse, and fewer still have exploited this to gain insight into the cognitive processes underpinning salient operational knowledge production. This paper draws upon a discussion from a multi-stakeholder workshop on bioaerosols and the built environment and draws upon Cognitive Linguistics to systematically examine the cognitive structuring of those different stakeholder representations. This approach is then explored as a contribution to good practice in air quality knowledge management and communication that is consistent with studies on cognitive and learning science and has potential for policy formulation.

Pollutants doi: 10.3390/pollutants5020016

Authors: Faik Hamad Sarita S. Nair Ruben Pinedo-Cuenca Seth J. Davis Tony John Stubbs Poo Balan Ganesan

In this paper, we analyse the effectiveness of microbubble technology in inactivating/reducing gram-negative, gram-positive, and radiation-resistant bacteria, including Escherichia coli, Bacillus subtilis, and Deinococcus radiodurans, respectively, in model water. Key water quality parameters such as dissolved oxygen, conductivity, pH, and total dissolved solids are recorded and presented to demonstrate their range in the current investigation. The study results indicate a reduction of 95% in E. coli, 100% in D. radiodurans, and 45% in B. subtilis following microbubble treatment. These findings suggest that ambient air microbubbles, generated using a low-cost, reagent-free, and eco-friendly venturi-type microbubble generator, represent a promising technique for reducing bacterial loads in water.

Pollutants doi: 10.3390/pollutants5020015

Authors: Marcus Monteiro Patrícia Santos Jorge Espinha Marques Deolinda Flores Manuel Azenha José A. Ribeiro

Active and abandoned mining sites are significant sources of heavy metals and metalloid pollution, leading to serious environmental issues. This study assessed the environmental risks posed by potentially toxic elements (PTEs), specifically arsenic (As) and antimony (Sb), in the Technosols (mining residues) of the former Pejão coal mine complex in Northern Portugal, a site impacted by forest wildfires in October 2017 that triggered underground combustion within the waste heaps. Our methodology involved determining the “pseudo-total” concentrations of As and Sb in the collected heap samples using microwave digestion with aqua regia (ISO 12914), followed by analysis using hydride generation-atomic absorption spectroscopy (HG-AAS). The concentrations of As an Sb ranging from 31.0 to 68.6 mg kg−1 and 4.8 to 8.3 mg kg−1, respectively, were found to be above the European background values reported in project FOREGS (11.6 mg kg−1 for As and 1.04 mg kg−1 for Sb) and Portuguese Environment Agency (APA) reference values for agricultural soils (11 mg kg−1 for As and 7.5 mg kg−1 for Sb), indicating significant enrichment of these PTEs. Based on average Igeo values, As contamination overall was classified as “unpolluted to moderately polluted” while Sb contamination was classified as “moderately polluted” in the waste pile samples and “unpolluted to moderately polluted” in the downhill soil samples. However, total PTE content alone is insufficient for a comprehensive environmental risk assessment. Therefore, further studies on As and Sb fractionation and speciation were conducted using the Shiowatana sequential extraction procedure (SEP). The results showed that As and Sb levels in the more mobile fractions were not significant. This suggests that the enrichment in the burned (BCW) and unburned (UCW) coal waste areas of the mine is likely due to the stockpiling of lithic fragments, primarily coals hosting arsenian pyrites and stibnite which largely traps these elements within its crystalline structure. The observed enrichment in downhill soils (DS) is attributed to mechanical weathering, rock fragment erosion, and transport processes. Given the strong association of these elements with solid phases, the risk of leaching into surface waters and aquifers is considered low. This work underscores the importance of a holistic approach to environmental risk assessment at former mining sites, contributing to the development of sustainable remediation strategies for long-term environmental protection.

Pollutants doi: 10.3390/pollutants5020014

Authors: Dele Raheem Marco Trovò Constanza Carmona Mora Clara Vassent

The threats posed by Persistent Organic Pollutants (POPs) impact food safety and, by implication, food security in the polar regions. POPs tend to persist in the environment and the fatty tissues of animals, thereby constituting long-term contamination. Due to the cold climate and geography of these polar regions, they create a sink for these pollutants, which travel from their source of production and accumulate in food chains, resulting in health risks to the ecosystem, animals, and humans of the Arctic and Antarctica. In this paper, we draw attention to the threats posed by POPs and how they can lead to food insecurity, negatively affecting health due to unsafe traditional foods. A narrative synthesis methodology was employed, systematically analyzing historical data, activities, and research trends on POP contamination in polar ecosystems. We also highlight resilience promoted by Arctic governance, with a focus on how the issues of POPs became an international matter from the 1970s, with three United Nations (UN) conventions: the UN-Environment Stockholm Convention on Persistent Organic Pollutants, the UN Minamata Convention on mercury, and the UN-ECE Convention on Long-range Transboundary Air Pollution. These conventions led to the start of several monitoring activities in the polar regions, transforming the POPs into a global topic. We also consider the intertwined effect of climate change on POPs. Additionally, the human rights paradigm in relation to food security and sovereignty for polar communities is explored. Strengthening the resilience of communities in the polar regions requires recognition of these nutritious traditional foods as an aspect of cultural identity that must be safe and easily accessible. We focus on developments, improvements, the role of international cooperation, and frameworks to assist in research and regulations. Furthermore, establishing systems that engage local communities to consistently monitor POPs regularly will lead to a better understanding of these threats. Ultimately, this narrative provides a look into the past and current research of POPs and their monitoring in the polar regions.

Pollutants doi: 10.3390/pollutants5020013

Authors: Abdul-Rahaman Afitiri Ernest Kofi Amankwa Afrifa Marion Martienssen

The use of ultraviolet (UV) for water disinfection is known for its chemical-free process and with no harmful disinfection by-products. Yet, the disinfection process remains time-consuming, and many studies are limited to disinfection of one or two microbial species. Direct photolytic and glass-embedded TiO2 photocatalytic disinfection of four different bacterial species (Staphylococcus aureus, Salmonella senftenberg, Bacillus subtilis, and Escherichia coli) were assessed using UV-LED radiation with wavelengths of 365 nm. The optimization of the UV disinfection under different masses of the TiO2 photocatalyst was evaluated. Additionally, the order of disinfection of the different bacteria species was assessed. The disinfection effects were measured based on the potential to reduce the number of bacteria species, calculated in colony-forming units/mL and log reduction units. The disinfection of Staphylococcus aureus was enhanced from 1.46 log reduction units in the UV-alone treatment to a high of 5.65 log reduction units in the UV + 0.08 g TiO2 treatment. Regarding Salmonella senftenberg, disinfection was enhanced from 1.26 log reduction units to 3.85 log reduction units in UV-alone experimental treatments and UV + 0.04 g TiO2, respectively. Similarly, an increase in Bacillus subtilis reduction was achieved from a low of 0.69 log reduction units to a high of 2.98 log reduction units in UV-alone treatments and UV + 0.08 g TiO2, respectively. The disinfection of Escherichia coli was enhanced from 2.49 log reduction units (UV-alone treatment) to a high of 6.35 log reduction units (UV + 0.02 g TiO2). The findings provide key implications and new insights into the studied bacteria species and the future application of porous glass-embedded TiO2 photocatalysts to enhance bacteria disinfection using UV light for improved water.

Pollutants doi: 10.3390/pollutants5020012

Authors: Issah Haruna Emmanuel Obeng-Gyasi

Chronic kidney disease (CKD) is a noteworthy global health issue affecting 10% of the world’s populace. It is increasingly linked to environmental exposures; however, the interplay of toxic metals, per- and polyfluoroalkyl substances (PFAS), and essential elements has not been fully elucidated. This cross-sectional study analyzed 5800 out of the 9245 participants from the 2017–2018 NHANES dataset to evaluate the combined effect of PFAS, essential elements, and toxic metals on CKD using logistic regression and advanced environmental mixture models, namely, Bayesian Kernel Machine Regression (BKMR), quantile g-computation (qgcomp), and Weighted Quantile Sum (WQS) regression. Our results showed cadmium (Cd) emerging as a significant contributor to CKD (OR = 2.16, p = 0.023) from the logistic regression analysis. Mercury (Hg) demonstrated the highest contribution in mixtures (posterior inclusion probability = 0.908) from our BKMR analysis, with a non-linear U-shaped dose–response relationship. Essential elements like selenium (Se) and manganese (Mn) exhibited protective correlations but complex non-linear interactions, moderating toxic metal effects from our qgcomp and WQS regression. Notably, antagonistic interactions between essential elements and some pollutants reduced the overall mixture impact on CKD, showing an overall decreasing joint effect of the combined PFAS, toxic metals, and essential elements on CKD, from the 25th to the 75th quantile. This study highlights the role of environmental co-exposures in CKD risk and highlights the need for advanced statistical and machine learning approaches in studying complex environmental mixture interactions on human health.

Pollutants doi: 10.3390/pollutants5020011

Authors: Dilpreet Sekhon Emanuel Alcala Jaymin Kwon Jason Bush Mary A. Garza

To investigate the place-based association between BCM and air pollution in middle-aged (45–64) and older-aged women (65+) in California at the zip code level, secondary data were collected from the California Department of Public Health (CDPH) Data and Vital Statistics, CalEnviroScreen 4.0, and the American Community Survey (ACS) from the Census. Multiple linear regression was used to test the significance between air pollution and age-standardized BCM rates. The results indicate a significant association between PM2.5 and age-standardized BCM rates for both the middle-aged and older-aged groups (β = 3.73, 95% CI [2.89, 4.58]; β = 5.33, 95% CI [2.75, 8.32], respectively). Furthermore, we found evidence of effect modification by the concentration of Hispanic women (β = −6.73, 95% CI [−9.37, −4.08]. This study provides evidence of a significant spatial association between PM2.5 and BCM rates, which has policy implications for stricter air quality regulations and urban planning policies. Further research is needed to establish causality and the mechanism of action at the population level.

Pollutants doi: 10.3390/pollutants5020010

Authors: Jyotish Kumar Mahesh Narayan

Perfluoroalkyl substances (PFAS), also known as “forever chemicals”, are a class of highly stable chemical compounds that slowly contaminate waterbodies and soil. The widespread presence of PFAS is associated with adverse human health effects and is a major environmental concern. The conventional, highly sensitive methods used for PFAS detection are LC-MS/MS and solid phase extraction, but they are very complex and expensive. Therefore, there is an urgent need for sensitive, low-cost, and fast methods for the detection and removal of PFAS compounds from water and soil resources. The advancement of nanotechnology has significantly impacted advanced disease diagnosis and treatment in the last few decades. Currently, these engineered nanomaterials (ENMs) have been exploited for the development of advanced nano-enabled techniques for the detection and removal of environmental pollutants. Nano-enabled techniques also offer improved performance over conventional methods. In this review, the details of the detection and removal of PFAS, as well as their optimization and limitations, and future perspectives are discussed. We focused on the implementation of nanomaterials such as nanoparticles, nanotubes, nanorods, and nano*filtration membranes for efficient PFAS detection and removal. We also included the recent literature and global guidelines for PFAS use and the effect of PFAS exposure on human health.

Pollutants doi: 10.3390/pollutants5020009

Authors: Edariane Menestrino Garcia Ronan Adler Tavella Livia da Silva Freitas Gabriella Mello Gomes Vieira de Azevedo Gustavo de Oliveira Silveira Vitoria Machado da Silva Ana Luíza Muccillo-Baisch Flavio Manoel Rodrigues da Silva Júnior

Exposure to contaminated soils can adversely affect health and the well-being of both humans and animals. Environmental stressors can influence the mobility and toxicity of contaminants, altering their potential impacts. This study aimed to assess the impact on the behavior of offspring from rats exposed during the gestation and lactation period to contaminated and acidified soils. Female Wistar rats were gavaged daily for 42 days with soil leachate from an industrial region known to be contaminated with metals and metalloids, using solvents with different pH values (6.0, 5.2, and 3.6). The offspring were evaluated in behavioral tests including Open Field, Elevated Plus Maze, and Inhibitory Avoidance. Our findings revealed significant statistical differences in all three tests conducted, indicating that the exposed groups exhibited lower exploratory behavior, higher anxiety behavior, and lower memory retention than the control groups. The difference was more pronounced in the soil leachate with acidified solvent, at both pH 5.2 and 3.6, suggesting that the combined effect of both stressors led to synergistic interactions, potentiating their impacts. Elemental analysis revealed elevated levels of neurotoxic metals, including Cr, Cu, and Ni, as well as the metalloid As, with acidification significantly enhancing their bioavailability. Moreover, our results demonstrate that acidification facilitated the mobilization of metals and the metalloid As, increasing their bioavailability and acting synergistically to exacerbate the behavioral impacts of contaminated soils. Special attention should be given to populations living in industrial areas that may be exposed to contaminated soils.

Pollutants doi: 10.3390/pollutants5010008

Authors: Ryunosuke Kikuchi Rosário Plácido Roberto da Costa Carla Sofia Santos Ferreira

The prevalence of hyperthyroidism in cats has been steadily increasing worldwide since the late 1970s. The main cause of feline hyperthyroidism remains unknown. The underlying cause was studied from the viewpoint of the “One Health” concept, which is an approach integrating environmental, animal and human health. Looking at the dietary difference between cats which are carnivores and dogs which appear to be omnivores like humans, there is a possibility that cats take in a comparatively greater amount of endocrine-disrupting chemicals such as polybrominated diphenyl ethers (PBDEs) than dogs and humans via the fish-based food web. PBDEs have been used worldwide as flame retardants since the 1970s. It is considered that PBDEs mimic thyroid-stimulating hormones to cause a thyroid adenoma, which is often active and produces excessive thyroid hormones, resulting in symptomatic hyperthyroidism. The increasing prevalence of feline hyperthyroidism may be associated with Minamata disease that was caused by methyl-mercury contamination in the 1950s. This environmental contamination firstly wreaked havoc as neurological disorders in local cats, and this occurrence was a sign that severe neurological disorders would next develop in large numbers of local people. The prevalence of feline hyperthyroidism may be a sign of what will next emerge in human beings.

Pollutants doi: 10.3390/pollutants5010007

Authors: Abu Bakar Siddique Abu Sayed Al Helal Teofanes A. Patindol Deejay M. Lumanao Kleer Jeann G. Longatang Md. Alinur Rahman Lorene Paula A. Catalvas Anabella B. Tulin Molla Rahman Shaibur

This study evaluated heavy metal (HM) contamination in sediments from the Malbasag River in the Ormoc City port, Leyte, Philippines. A total of thirty sediment samples were collected randomly from ten locations along the river using an Ekman grab sampler. Atomic absorption spectrophotometry revealed HM concentrations in the order of Mn > Zn > Cu > Ni > Pb > Cd. All HMs exceeded their sediment quality guideline (SQG) thresholds except for Mn. Contamination was assessed using indices such as the contamination factor (CF), pollution load index (PLI), geo-accumulation index (Igeo), and enrichment factor (EF). The CF values indicated “moderate to considerable” contamination for Zn, Ni, and Cd, while Cu and Pb showed “very high” contamination levels. The PLI results indicated severe sediment degradation in 20% of samples. The Igeo analysis classified 60% of the samples as “heavily to extremely polluted” for Cd, Cu, and Pb. EF analysis suggested that anthropogenic sources contributed to elevated HM levels, including port activities and agricultural runoff. Ecological risk index (RI) analysis revealed moderate risk in 40% and considerable risk in 20% of sampling locations. Multivariate analyses suggested significant anthropogenic contributions to HM contamination, highlighting the need for further studies to assess the ecological impacts.

Pollutants doi: 10.3390/pollutants5010006

Authors: Constance Chifuniro Utsale Chikumbusko Chiziwa Kaonga Fabiano Gibson Daud Thulu Petra Chiipa Stellah James Ishmael Bobby Mphangwe Kosamu

The recent increase in industrial activities has raised concerns regarding environmental quality in urban areas in Malawi. In this study, the contents of heavy metals [copper (Cu), zinc (Zn) and cadmium (Cd)] were analysed in 15 sites selected from Makata, Limbe, Maselema, Chirimba, and Maone industrial zones of Blantyre City in Malawi. Soil sampling was conducted during dry and rainy seasons, followed by laboratory analysis. The results revealed a few cases of elevated content of heavy metals exceeding permissible England and Canadian standards with higher content detected during the dry season than in the rainy season. Chirimba soil had the highest mean Zn content of 822 mg/kg in the rainy season and 579 mg/kg in the dry season. Maone soils had the highest Cd content, measuring 2.09 mg/kg in the rainy season and 3.06 mg/kg in the dry season. Chirimba soils also had the highest Cu content with levels of 105 mg/kg in the dry season and 79 mg/kg in the rainy season. The geo-accumulation index indicated that Zn posed the most severe pollution. The results of the Positive Matrix Factorisation model suggest that heavy metal pollution primarily originates from metal processing and manufacturing industries, followed by plastic manufacturing industries. This finding is supported by the nature of emissions from these sectors, where metal processing activities release heavy metals through particulates and waste to the environment, suggesting collective actions to prevent soil contamination.

Pollutants doi: 10.3390/pollutants5010005

Authors: Carlos Armenta-Déu

This paper focuses on the environmental impact of urban surface transportation and the influence that driving mode and drivers’ attitudes have on it. This article emphasizes the importance of a respectful attitude toward the environment and adopting moderate or conservative driving modes. This study covers driving GHG emissions in urban and peripheral areas for variable driving conditions, evaluating reductions or increases in CO2 emissions depending on the way of driving. The analysis of the different cases shows that pollutant emissions are significantly lower if a car driver reduces the acceleration rate and slows down by 10 to 20 km/h, or 6 to 12 mph, depending on the urban zone, downtown or peripheral, and traffic conditions. The reduction in GHG emissions can be as high as 0.083 kg of CO2 per day, on average, representing a global yearly reduction of 30 kg of GHG emissions per vehicle. This paper analyzes how inadequate driving speed and the above traffic regulation limits have caused a surplus in GHG emissions and a severe impact on urban areas, which are sensitive to pollution, increasing the GHG emission rate by between 28% and 40% depending on driving mode and driver attitude. This study shows that vehicle speed reduction did not significantly increase traveling time, with an average time extension of 0.2 min per km, representing a global extended daily traveled time of 6.4 min for the average daily journey distance in many countries. GHG increases due to inadequate driving increase the early human mortality rate by 0.4%, representing nearly 35 million early deaths per year.

Pollutants doi: 10.3390/pollutants5010004

Authors: Chrysoula Chrysakopoulou Elina Aidona Dimitrios Vogiatzis Alexandros Drakoulis Lambrini Papadopoulou Nikolaos Kantiranis

Two sets of sediment samples were collected from the Sarigiol basin, Greece, aiming to evaluate the environmental consequences of the industrial activity in the area by assessing their magnetic properties with the magnetic susceptibility method. Chemical composition and morphological characteristics of magnetic particles were defined by EDX analysis and scanning electron microscopy, respectively. Based on the results, most of the study area shows positive values of the difference between XLF values of the samples, indicating the influence of fly ash dispersion from Agios Dimitrios and Kardia power plants and the conveyor belt, down to a depth of 50 cm. Negative values in the NE, W and S parts of the study area are attributed to ophiolite complexes. Anthropogenic and lithogenic magnetic particles were identified at a 50 cm depth, in the form of spheres and octahedrons, respectively. Fe is the dominant element while Al, Si, Mg and Ca were found in minor amounts. Cr increases with depth, pointing mainly to a lithogenic source, while Ti decreases, suggesting a relationship with the dispersed fly ash particles. Mn and Zn were found in limited magnetic spheres. These findings highlight the need for effective environmental management strategies and are valuable keys for soil pollution control.

Pollutants doi: 10.3390/pollutants5010003

Authors: Hugo Ramírez-Aldaba Pablito Marcelo López-Serrano Emily García-Montiel Miriam Mirelle Morones-Esquivel Melissa Bocanegra-Salazar Carlos Borrego-Núñez José Manuel Loera-Sánchez

Air pollution in urban centers comes from anthropogenic activities. Tropospheric ozone (O3) depends on chemical precursors that promote an increase in its production, mainly in wind-dominated and large green areas. It is a gas produced by a series of complex chemical reactions catalyzed by sunlight in the atmosphere. It can be concentrated to a greater or lesser extent depending on factors such as the amount of volatile organic compounds (VOCs), the amount of nitrogen dioxide (NO2), the intensity of solar radiation, or by climatic conditions such as temperature and other factors. The objective of this study was to predict tropospheric ozone levels from Land Surface Temperature (LST) data of Landsat 8 in the city of Durango, Dgo. Tropospheric O3 and LST values were obtained from 14 sampling points in the urban area of the city of Durango, of which 11 were obtained by collecting from temperature-monitoring station data and the rest from three fixed monitoring stations established in the city, specifically located in Ministry of Natural Resources and Environment (SRNyMA), Durango Institute of Technology (ITD) and Interdisciplinary Research Center for Regional Integral Development Durango Unit (CIIDIR). A correlation analysis was performed for the 12 months of the year 2023. Subsequently, a linear regression analysis was executed for each month. The results showed a greater positive correlation between O3 concentration and temperature for January (r = 0.91); additionally, this period showed a greater goodness of fit in the prediction of O3 (R2 = 0.91; RMSE = 0.65 ppm). The LST allows for the spatial prediction of ozone concentrations in terms of covering complete urban areas without measuring air stations.

Pollutants doi: 10.3390/pollutants5010002

Authors: Masha Pitiranggon Sarah Johnson Ariel Spira-Cohen Holger Eisl Kazuhiko Ito

Differences in exposures and resources to manage personal health contribute to persistent inequities in air pollution burden despite vast air quality improvements over the past 2–3 decades in the United States. These factors are, partly, linked to historic racist practices, such as redlining, a discriminatory housing policy that was practiced legally between 1935 and 1968. Using 100 m × 100 m resolution land-use regression predicted surfaces of PM2.5 constituents (black carbon, nickel, vanadium, and copper) as pollution source indicators, we fit Bayesian generalized linear mixed-effects models to examine differences in source exposures over two study periods, 2008–2015 and 2016–2019, comparing (1) redlined to not redlined and (2) high-asthma to low-asthma neighborhoods. We examine redlining as an indicator of historical, and structural racism and asthma rates as an indicator of present-day community burden. Redlined areas saw near elimination of disparities in exposure to residual oil boilers and marine residual oil but persistent disparities in traffic. High-asthma neighborhoods continue to have disproportionately high exposures to both residual oil boilers and traffic, with no discernable disparities related to marine residual oil emissions. Overall exposure disparities are small, with PM2.5 disparities by both asthma morbidity and redlining amounting to less than 1 µg/m3 and NO2 disparities by asthma and redlining amounting to less than 2 ppb in the post-2016 period. For context, 2019 NYC average PM2.5 and NO2 were 8.5 µg/m3 and 20 ppb, respectively. Our findings suggest that local pollution policy should focus on reducing traffic and building boiler emissions in high-asthma neighborhoods to reduce exacerbations.

Pollutants doi: 10.3390/pollutants5010001

Authors: Christopher Power

Acid mine drainage (AMD), which is primarily caused by the exposure of sulfidic minerals to oxygen and water during mining operations, remains a significant contributor to environmental pollution. Numerous technologies have been developed to prevent/control and treat AMD, including the isolation of waste from the atmosphere and treatment systems for AMD-impacted water. Many field studies on mine site reclamation have involved an individual AMD source and/or technology, with a limited number of studies looking at reclamation programs integrating multiple approaches to manage AMD stemming from both surface and underground sources. The former Franklin mine site in Nova Scotia, Canada, was impacted by the deposition of waste rock across the site and the discharge of mine water from underground workings, with the adjacent Sullivan’s Pond serving as the main environmental receptor. Site reclamation was completed in 2010 and involved the following: (1) excavation of the dispersed waste rock (117,000 m2) and backfilling with clean soil; (2) consolidation of the excavated waste rock into a covered, compact waste rock pile (WRP) (25,000 m2); and (3) construction of a passive treatment system for the discharging underground mine water. An extensive field sampling program was conducted between 2011 and 2018 to monitor a range of meteorological, cover material, waste rock, groundwater, and surface water quality parameters. The results confirm that the multi-layer, geomembrane-lined WRP cover system is an extremely effective barrier to air and water influx, thereby minimizing the rate of AMD generation and seepage into groundwater and eliminating all contaminated surface water runoff. A small AMD groundwater plume emanates from the base of the WRP, with 50% captured by the underground mine workings over the long term and 50% slowly migrating towards Sullivan’s Pond. Excavation of the former waste disposal area eliminated the AMD source from the previously dispersed waste, with only clean surface water runoff and a diminishing legacy groundwater plume remaining. Finally, the passive treatment system, which contains a series of treatment technologies such as a limestone leach bed and settling pond, successfully treats all mine water loading (~50 kg/day) discharging from the underground workings and surface runoff. Its additional treatment capacity (up to ~150 kg/day) ensures it will be able to manage any potential drop in treatment efficiency and/or increased AMD loading from long-term WRP seepage. This comprehensive study of mine site reclamation and AMD management at an abandoned mining site can be of great reference value for environmental management and policymakers in the mining sector.

Pollutants doi: 10.3390/pollutants4040035

Authors: Sinazo Ajibade Barbara Simon Anita Takács Miklós Gulyás

Cigarette butts (CBs) are emerging soil contaminants, releasing chemicals upon contact with moisture. This study examined heavy metal concentrations leached from smoked and unsmoked CBs (Pall Mall, Philip Morris, and Marlboro) into OECD artificial soil and Vertisol soil and their accumulation in white mustard (Sinapis alba L.). Key physiological parameters, including germination rate, plant height, fresh weight, and dry weight, were analyzed, along with the uptake of heavy metals (Al, Fe, Mn, Zn, Ba, Ti, and Cu) and essential elements (Ca, Mg, Na, and K). Results showed that Mn had the highest bioaccumulation index (BAI = 1.10) in OECD soil, while Zn uptake was consistently high across soil types. Soil type significantly influenced plant height (χ2 = 41.269, p < 0.01) and elemental composition, with Vertisol soil facilitating greater overall growth and heavy metal uptake than OECD soil. MANOVA revealed no three-way interaction among soil type, CB use, and CB brand on elemental uptake. However, two-way interactions, particularly between soil type and CB use (F (4, 39) = 40.233, p < 0.001, Wilk’Λ = 0.195), showed significant effects on heavy metal uptake. These findings highlight the complex interactions influencing plant contamination, underlining the ecological risks of CB pollution in soils.

Pollutants doi: 10.3390/pollutants4040034

Authors: Adarsh Sankaran Susan Mariam Rajesh Muraleekrishnan Bahuleyan Thomas Plocoste Sumayah Santhoshkhan Akhila Lekha

Analyzing the fluctuations of particulate matter (PM) concentrations and their scaling correlation structures are useful for air quality management. Multifractal characterization of PM2.5 and PM10 of three cities in India wase considered using the detrended fluctuation procedure from 2018 to 2021. The cross-correlation of PM concentration in a multifractal viewpoint using the multifractal cross-correlation analysis (MFCCA) framework is proposed in this study. It was observed that PM2.5 was more multifractal and complex than PM10 at all the locations. The PM–gaseous pollutant (GP) and PM–meteorological variable (MV) correlations across the scales were found to be weak to moderate in different cities. There was no definite pattern in the correlation of PM with different meteorological and gaseous pollutants variables. The nature of correlation in the pairwise associations was found to be of diverse and mixed nature across the time scales and locations. All the time series exhibited multifractality when analyzed pairwise using multifractal cross-correlation analysis. However, there was a reduction in multifractality in individual cases during PM–GP and PM–MV paired analyses. The insights gained into the scaling behavior and cross-correlation structure from this study are valuable for developing prediction models for PMs by integrating them with machine learning techniques.

Pollutants doi: 10.3390/pollutants4040033

Authors: Awnon Bhowmik Goutam Saha Suvash C. Saha

Microplastics, defined as plastic particles less than 5 mm in size, have become a pervasive environmental contaminant detected across a wide range of ecosystems. While the presence of microplastics in marine life and humans has been extensively documented, there remains a significant gap in understanding their full health impacts. Moreover, the effects of microplastics on animals, particularly those in close proximity to human activities, remain underexplored, representing a key area for future research. In this study, we found high levels of microplastic accumulation in animal tissues, particularly in the lungs, intestines, and reproductive organs. Our results also indicate that ingestion of microplastics occurs through multiple environmental sources, including contaminated food, water, and air, reflecting their widespread distribution. Evidence of microplastics crossing biological barriers and accumulating in critical organ systems suggests potential long-term health risks for animals that may also have implications for humans through environmental and food-chain exposure. Given the interconnectedness of ecosystems and the potential for these contaminants to enter the food chain, the presence of microplastics in animals raises serious concerns for broader ecological and human health. The findings underscore the urgent need for further research to clarify the long-term effects and to develop effective strategies for mitigating this emerging global threat.

Pollutants doi: 10.3390/pollutants4040032

Authors: Justin B. Richardson Minh Tri Truong Annise M. Dobson

Atmospheric pollution of metals negatively impacts the health of terrestrial and aquatic plants and animals. Despite implementation of policies that have substantially decreased emissions of metal pollutants, their legacy continues in temperate forest ecosystems across the globe. Here, we evaluated throughfall and litterfall concentrations and fluxes of Cu, Zn, Cd, and Pb via in rural temperate forests along the Appalachian Mountain range in eastern United States. Our five years of data show that throughfall fluxes of Cu, Cd, and Pb have decreased >89% since the 1980s. However, throughfall Zn and litterfall Cu, Zn, and Cd fluxes remain comparable or greater than the 1980s. These results suggest that Cd, Cu, and Pb emissions have decreased, but trees retain and recycle Cd, Cu, and Zn pollution, extending their legacy for decades following the emission.

Pollutants doi: 10.3390/pollutants4040031

Authors: Claudia I. Rivera-Cárdenas Thiare Arellano

The Tula industrial area in Central Mexico comprises, among other industries, a refinery and a thermoelectric power plant. It is well known for its constant emissions of gases into the atmosphere and considered an important area where pollutants released into the atmosphere have an influence on local and regional air quality. During March and April 2017, a field campaign was conducted with the objective of quantifying formaldehyde (HCHO), sulfur dioxide (SO2), and nitrogen dioxide (NO2) emissions from this industrial area using mobile differential optical absorption spectroscopy (DOAS) instruments. Calculated average emissions of the Francisco Perez Rios Power Plant and the Miguel Hidalgo Refinery were 3.14 ± 2.13 tons per day of HCHO, 362.08 ± 300.14 tons per day of SO2, and 24.76 ± 12.82 tons per day of NO2. From the measurements conducted, the spatial distribution patterns of SO2, NO2, and HCHO were reconstructed, showing a dispersion pattern of SO2 and NO2 towards the southwest of the industrial complex, impacting agricultural and urban areas. Occasionally, and usually during the morning hours, SO2 and NO2 were dispersed towards the north or northeast of the industrial complex. In the case of HCHO, dispersion was observed towards the south and southeast of the industrial complex. The far-reaching implications of this study are that for the first time, formaldehyde emissions were quantified. In addition, a follow-up study was conducted regarding nitrogen dioxide and sulfur dioxide emissions from the Tula Industrial area.

Pollutants doi: 10.3390/pollutants4040030

Authors: Yuanyuan Dai Yubo Dong Huimin Wu Zilong Chen Feng Yang Jia Jia Zhongzhi Chen

Nitrite is a common pollutant in marine environments and can cause mortality in crustaceans and bivalves. The purpose of the current study is to understand nitrate’s toxicity to juvenile clams due to its potential impact on aquaculture and marine ecosystems. Juvenile sunray surf clams (Mactra chinensis Philippi) (1.00 ± 0.10 cm shell length, 0.75 ± 0.04 cm shell height) were exposed to varying concentrations of nitrite for 96 h and 20 days, respectively. The LC50 for survival at 96 h was 37 mg/L NO2-N. Histological evaluations were made on juvenile clams exposed at 30 mg/L after 20 d of exposure. Epithelial cells and digestive diverticulum are the best sub-lethal effect indicators. Shell length and antioxidant enzyme activities were measured at the beginning of the experiment and then observed 10 and 20 days after exposure. A logarithmic relationship was obtained between the relative growth rate (based on the shell length) of juvenile M. chinensis and the nitrite concentration. Compared to the control, activity suppression of superoxide dismutase and catalase activity was detected from the concentration of 1 mg/L NO2-N. It is recommended that nitrite concentrations remain below 1 mg/L to prevent stress during the early developmental stages of clams.

Pollutants doi: 10.3390/pollutants4030029

Authors: Volodymyr Laptiev Michelle Giltrap Furong Tian Nataliia Ryzhenko

This work aims to assess the bioavailability and bioaccumulation of Cr, Cu, Pb, and Zn in the soil–plant system (Erigeron canadensis L.) in the zone of anthropogenic impact in Dnipro city, a significant industrial and economic centre of Ukraine. Sampling was carried out at three locations at distances of 1.0 km, 5.5 km, and 12.02 km from the main emission sources associated with battery production and processing plants in Dnipro. The concentrations of heavy metals such as Cr, Cu, Pb, and Zn were analysed using atomic emission spectrometry from soil and parts of Erigeron canadensis L. The highest concentrations of elements in the soil, both for the mobile form and the total form, were determined to be 48.96 mg kg−1 and 7830.0 mg kg−1, respectively, for Pb in experimental plot 1. The general ranking of accumulation of elements in all experimental plots, both for the plant as a whole and for its parts, was as follows: Zn > Cu > Cr > Pb. Zn for plants was the most available heavy metal among all studied sites and had the highest metal content in the plant (339.58 mg kg−1), plant uptake index (PUI-506.84), bioabsorption coefficient (BAC-314.9), and bioconcentration coefficient (BCF-191.94). According to the results of the study, it is possible to evaluate Erigeron canadensis L. as a hyperaccumulator of Zn, Cu, and Cr and recommend it for phytoextraction of soils contaminated with Zn, Cu, and Cr and phytostabilization of soils contaminated with Pb.

Pollutants doi: 10.3390/pollutants4030028

Authors: Marina Ziliotto José Artur Bogo Chies Joel Henrique Ellwanger

The emergence of infectious disease outbreaks and ‘superbugs’ related to pollution combined with climate change is a current problem, not just a future threat. In May 2024, an extreme flood hit the Rio Grando Sul State, southern Brazil, triggering an important leptospirosis outbreak in urban settings with deficient sanitation systems. This and other cases discussed in this article exemplify how extreme weather events exacerbate the consequences of environmental pollution by multiple classes of pathogens in the global scenario of increasing anthropogenic pressures on the environment. A combination of actions to combat climate change and improvements in sanitation systems is essential to mitigate this problem.

Pollutants doi: 10.3390/pollutants4030027

Authors: Andrea Baldi Andrea Pronti Massimiliano Mazzanti Luisa Pasti

Aquaculture and waste valorization have the potential to show solid achievements toward food security and improvements in the circularity of resources, which are crucial aspects of achieving a sustainable lifestyle in agreeance with Agenda 2030 goals. This study aims to optimize and simplify the decision-making processes for the valorization of marine wastes (natural and from aquaculture) as secondary raw materials to produce high-value-added market goods. However, significant concentrations of pollutants may be present within wastes, compromising overall quality, and social dynamics can hinder their usage further. Goro’s lagoon was chosen as a case study, where the relations between the ecosystem services, a thriving bivalve economy, and social dynamics are deeply rooted and intertwined. Therefore, in the manuscript cost–benefit and foresight analyses are conducted to determine the best usage for algal biomass considering pollution, social acceptance, and profitability. These analyses are virtually conducted on bio-refineries that could be operating in the case study’s area: briefly, for a thirty-year running bio-plant, the CBA indicates the two best alternatives with an income of 5 billion euros (NPV, with a 5% discount rate) for a biofuel-only production facility, and a half for a multiproduct one, leading to the conclusion that the first is the best alternative. The foresight, instead, suggests a more cautious approach by considering external factors such as the environment and local inhabitants. Hence, the main innovation of this work consists of the decision-maker’s holistic enlightenment toward the complexities and the hidden threats bound to this kind of closed-loop efficiency-boosting process, which eventually leads to optimized decision-making processes.

Pollutants doi: 10.3390/pollutants4030026

Authors: Dale R. Van Stempvoort Susan Brown Priyantha Kulasekera Pamela Collins

Application of hydraulic fracturing to produce “unconventional” oil and gas from shale formations and other low-permeability geological units has raised concerns about the potential environmental impacts, including potential adverse effects of fracturing fluids (FF) on groundwater. In this study, laboratory batch test experiments and new analytical methods were developed to analyze FF chemicals as potential indicators (tracers) to detect impacts of fracturing fluids on groundwater. The tests, conducted over 101–196 days, included FF with synthetic chemicals (~40,000–4,000,000 µg/L), placed in batches with groundwater and sediment at 5° and 25 °C, along with sterile controls. Using the new methods, measurable concentrations of the FF chemicals were many orders in magnitude lower (~3000 to 3,000,000 X) compared to their concentrations in synthetic fracturing fluids, indicating that these chemicals are excellent candidates as indicators of FF contamination in groundwater, if they are relatively persistent, and not prone to extensive loss by sorption during migration in the subsurface. Variable sorption and degradation of the chemicals was observed in both batch and column tests. Sorption was negligible (sorption coefficient, Kd~0.0) for some synthetic chemicals (polyethylene glycol, ethanolamines, isopropanol, and ethyl hexanol) in some tests. At the other extreme, strong sorption was observed for some of the higher molecular weight cocamido propyl betaine (max Kd = 1.17) and polyethylene glycol (max Kd = 1.12) components, and triethanolamine (max Kd = 0.47) in other tests. Apparent loss by degradation was observed for each chemical in some tests, but negligible in others. The shortest apparent half-lives were for isopropanol and ethyl hexanol at 25 °C (t½ < 11 days), and the most persistent synthetic chemicals were polyethylene glycols (t½ ≥ 182 d) and the ethanolamines (t½ ≥ 212 d). Of the potentially diagnostic FF chemicals investigated, the relatively hydrophilic and persistent lower molecular weight polyethylene glycols are some of the most promising as potential indicators of contamination of groundwater by FF.

Pollutants doi: 10.3390/pollutants4030025

Authors: Zequn Li Heinz-R. Köhler Rita Triebskorn

In the present study, the toxicity of nicosulfuron to Danio rerio embryos was evaluated in three experiments through standardized toxicity tests according to OECD TG236 guidelines. In the first experiment, six concentrations of nicosulfuron (0, 0.1, 1, 10, 100, 1000 mg/L) were tested under optimal conditions (26 °C, pH 7.0) to assess the general sensitivity of zebrafish embryos to nicosulfuron. The second and third experiment examined the effects of different pH levels (5.0 and 9.0) and temperatures (21 °C and 31 °C) on the toxicity at four nicosulfuron concentrations (0, 10, 100, 1000 mg/L). Additionally, the sub-organismic effects of nicosulfuron on stress protein levels (Hsp70) of fish embryos were analyzed. Throughout the embryo experiments, no malformations were observed in all experiments. The survival rate exceeded 80% in all groups except for the 21 °C (pH 7.0) treatment groups. No significant effect of nicosulfuron on the survival rate was found at the same temperature or pH (p > 0.05). No significant difference in the heart rate was found among all nicosulfuron groups (p > 0.05) at 21 °C. The heart rate of fish embryos at 31 °C, pH 5.0 and pH 9.0 increased with nicosulfuron concentrations. Except for the pH 5.0 (26 °C) and 21 °C (pH 7.0) treatment groups, nicosulfuron was found to increase the hatching rate of embryos in other treatments; however, the corresponding times of action were different. At 21 °C (pH 7.0), the embryos did not hatch until 144 h post-fertilization. In terms of proteotoxicity, nicosulfuron was found to be more toxic to zebrafish embryos in the 21 °C, pH 5.0 and pH 9.0 treatment groups. However, at 31 °C, no significant difference in Hsp70 levels was found among all the different nicosulfuron concentrations (p > 0.05). Our results show that nicosulfuron exerts a weak toxicity to zebrafish embryos; however, this toxicity is amplified by inappropriate pH or temperature conditions.

Pollutants doi: 10.3390/pollutants4030024

Authors: Sarah G. Lindgren Laura J. Sakol Monica Hoover Timothy M. Raymond Dabrina D. Dutcher

While many sources of contamination in chemical and biological laboratories are well understood and known, some are less so. To quantify the magnitude of the potential contamination of solutions by zinc in common laboratory syringes, a study was conducted on solutions stored in rubber-containing syringes in which the rubber was catalyzed by zinc. This study identified specific factors contributing to contamination from laboratory syringes, including the syringe brand, time, solution type, and pH. Two common syringe brands, Covidien and BD, were tested, and three time durations, 0 days, 1 day, and 14 days, were examined. The solutions tested included sucrose and tartaric acid, representing both covalent and ionic species. Additionally, this study employed a pH range of 2 to 13 to further explore zinc contamination across a wide range of conditions and factors. The zinc concentration from the syringes was measured using inductively coupled plasma mass spectrometry (ICP-MS). The results, which ranged from less than 20 to over 600 μg L−1, revealed increased zinc concentration at both extreme pH values, while remaining lower but measurable at neutral pH levels. Zinc contamination is important to study because its contamination in laboratory syringes could interfere with the detection of other elements, further skew laboratory data, unexpectedly catalyze reactions, and lead to inconsistencies in experimental conditions. This study further emphasizes the broader significance of understanding pollutants within laboratory settings. The findings highlight the intricate dynamics of zinc contamination, stressing the need for the control of environmental factors and the broad dissemination of lesser-known sources. Recognizing the potential impact of contaminants like zinc is crucial, as it not only influences analytical accuracy, but also mirrors the wider concern of pollutants compromising scientific integrity in diverse experimental conditions.

Pollutants doi: 10.3390/pollutants4030023

Authors: Mahboobe Safari Sinegani Maria Manzoor Karl Hermann Mühling

Cadmium accumulation in wheat as a daily food, even in low concentrations, is a serious threat to human health. Previous studies have reported conflicting results on the impact of calcium treatments on cadmium uptake and translocation in plants due to the complex soil conditions. Our hydroponic study offers clearer insights into how specific calcium treatment parameters influence cadmium uptake and translocation in wheat. The hydroponic medium was contaminated by cadmium (CdCl2) and the following treatments were applied: CaCO3, CaSO4, CaCl2, CaCO3 + CaSO4, CaCO3 + CaCl2, and CaSO4 + CaCl2. After harvesting, the wheat was analyzed for Cd2+ uptake characteristics including translocation factor, bioconcentration factor, and uptake. Furthermore, physiological growth parameters and plant nutrients were also determined. Applying CaCO3 significantly decreased wheat Cd2+ concentration by about three times in CaCO3 and two times in CaCO3 + CaSO4 and CaCO3 + CaCl2 treatments than in Cd-control. This study clearly elucidates that pH and CO32− were crucial in reducing Cd2+ concentration in wheat. SO42−, Cl−, and Ca2+ showed no effect on Cd2+ concentration. Ca2+ only reduced the translocation factor (TF) of Cd2+ in plants. CaCO3 also declined cadmium interference in the Mg2+, Mn2+, and Cu2+ uptake. Therefore, this study provides novel insight into the pure effects of calcium treatments on controlling cadmium contamination in plants, independent of soil effect.

Pollutants doi: 10.3390/pollutants4030022

Authors: Selman Karagoz

End-of-life vehicle (ELV) forecasting constitutes a crucial aspect of sustainable waste management and resource allocation strategies. While the existing literature predominantly employs time-series forecasting and machine learning methodologies, a dearth of studies leveraging deep learning techniques, particularly Long Short-Term Memory (LSTM) networks, is evident. Moreover, the focus on localized contexts within national or municipal boundaries overlooks the imperative of addressing ELV generation dynamics at an international scale, particularly within entities such as the EU-27. Furthermore, the absence of methodologies to reconcile missing historical data presents a significant limitation in forecasting accuracy. In response to these critical gaps, this study proposes a pioneering framework that integrates grey systems theory (GST)-based backcasting with LSTM-based deep learning methodologies for forecasting ELV generation within the EU until 2040. By introducing this innovative approach, this study not only extends the methodological repertoire within the field but also enhances the applicability of findings to supranational regulatory frameworks. Moreover, the incorporation of backcasting techniques addresses data limitations, ensuring more robust and accurate forecasting outcomes. The results indicate an anticipated decline in the recovery and recycling of ELVs, underscoring the urgent need for intervention by policymakers and stakeholders in the waste management sector. Through these contributions, this study enriches our understanding of ELV generation dynamics and facilitates informed decision-making processes in environmental sustainability and resource management domains.

Pollutants doi: 10.3390/pollutants4030021

Authors: Melanie M. Marshall Stephen J. Jacquemin Aubrey L. Jaqueth

The use of stable isotopes, specifically δ18OPO4 ratios, in differentiating potential sources of inorganic phosphorus (e.g., wastewater, septic, wild animals, domesticated animals, livestock, substrates, or commercial fertilizers) to watersheds is a growing field. This method produces data that, used in conjunction with statistical mixing models, enables a better understanding of contributing sources of runoff. However, given the recent development of this research area there are obvious limitations that have arisen, due in large part to the limited available reference data to compare water samples. Here, we attempt to expand the availability of reference samples by applying stable isotope methods to three types of common agricultural manures: poultry, dairy, and swine. We also aim to concatenate the organic waste literature on this topic, creating a more robust comparison database for future study and application in phosphorus source partitioning research. Among our samples, δ18OPO4 ratios for poultry were considerably elevated compared to dairy and swine manures (values of 18.5‰, 16.5‰, and 17.9‰, respectively). Extending this to other published ratios of δ18OPO4 from various types of waste products (e.g., septic, wastewater, livestock, other animals), a total range from 8.7‰ to 23.1‰ emerged (with existing poultry manure samples also ranking among the highest overall). Variation among samples in the larger dataset demonstrates the need for a further compilation of δ18OPO4 ratios for various types of waste, especially specific to geographic regions and watershed scales. With an increased sample size, the statistical strength associated with these methods would greatly improve.

Pollutants doi: 10.3390/pollutants4030020

Authors: Murilo G. Machado Julia F. G. Orrutéa Carolina Panis

A 2018 report from the Water Quality for Human Consumption Vigilance Information System (SISÁGUA, Brazil) showed the presence of 27 pesticides in Brazilian drinking water, of which 11 have carcinogenic potential. We assessed the data for 27 municipalities in Paraná state southwest, a rural landscape with high cancer rates. We selected data from the carcinogenic potential of 11 pesticides provided by international agencies (alachlor, aldrin-diheldrin, atrazine, chlordane, DDT, diuron, glyphosate, lindane, mancozeb, molinate, and trifluralin) and estimated the number of cancer cases attributable to drinking water contamination by pesticides. Also, we correlated such findings with incidence and mortality cancer rates for ten topographies obtained from the Brazilian National Cancer Institute (INCA) database. A total of 9 cities were selected, corresponding to about 81,000 people. All towns had all pesticides quantified in the drinking water. About ten cancer cases were attributed to drinking water contamination by pesticides in 2014–2017, mainly linked to diuron and mancozeb. Concerning the consolidated incidence of cancer cases reported by the INCA, significant correlations were found regarding aldrin-diheldrin, alachlor, and atrazine for breast cancer, atrazine for prostate cancer, and mancozeb and diuron for colon cancer, among others. Regarding the consolidated mortality rates, some correlations were found between DDT and trifluralin for the breast, DDT and lindane for the prostate, and glyphosate for lung cancer. Moderate correlations were found between the estimated and consolidated cancer cases for several topographies. Our findings highlight the correlation between drinking water contamination in Paraná state southwest and its increased incidence of cancers with poor prognosis.

Pollutants doi: 10.3390/pollutants4020019

Authors: Nontobeko Gloria Maphuhla Opeoluwa Oyehan Oyedeji

Soil contamination by metallic components is an obscure, detrimental, protracted, and irreparable predicament. Dumping of waste containing heavy metals into landfills, fertilizer and pesticide application, and coal combustion results in high toxicity of metallic elements, and their continuous accumulation in soil pollutes the environment, which, in turn, poses a threat to human health. The specimens were subsequently dehydrated, processed for mineralization, and carefully examined microscopically by scanning electron microscopy and energy-dispersive X-ray spectroscopy (SEM/EDX), which examined their mineral substance, crystalline configuration, and chemical composition. Thirteen (13) elements were detected, and only eight (8) metals were discovered (K, Mg, Na, Ca, Al, Fe, Au, Ba), including non-metals (C, O, Cl, P) and a metalloid (Si). The concentrations of possibly toxic elements obtained showed no consistent succession, as they fluctuated across the examined sites. The Al concentration ranged from 3.78 ± 0.23 wt% to 10.23 ± 0.31 wt%, while the Fe concentration fluctuated from 4.14 ± 0.40 wt% to 13.13 ± 1.07 wt%. Na and Mg levels were present in all samples, but their availability was minimal, at less than 2.0 wt%, ranging between 1.44 ± 0.20 wt% and 0.31 ± 0.08 wt%. The concentrations of Ca and K were low in all soil samples, ranging from 0.91 ± 0.14 wt% to 5.56 ± 0.47 wt% for Ca and from 1.32 ± 0.25 wt% to 4.87 ± 0.18 wt% for K. During the investigation at the designated and control areas, it was discovered that the concentrations of potentially hazardous metals exceeded the accepted limits established by the World Health Organization (WHO) > 100 ppm. The findings provide proof of metallic contaminants in the study region, which calls for proper monitoring, management, and remedial measures of metal-tainted sites, since the residents of this locality are at a significantly elevated risk of experiencing adverse effects due to their heightened exposure to these elements. As a result of that, there is an imperative need to monitor and regulate this area regularly and appropriately. The study recommends sustainable farming practices, where farmers could use natural fertilizers and compost, as well as, the implementation of proper waste management, effective recycling techniques, and proper disposal of substances containing heavy metals as byproducts. Further implement remediation techniques that effectively and safely restore soils contaminated by metals in an environmentally sustainable and economically efficient manner.

Pollutants doi: 10.3390/pollutants4020018

Authors: Franco Hernan Gomez Natalia Pelegri Juan Guillermo Lopez Kelly Cristina Torres Mentore Vaccari

Artisanal small-scale gold mining (ASGM) using mercury affects community agreements for the conservation of forests (CoS) and lakes (CoH), which have a high level of biodiversity in the Peasant Reserve Zone of the Cimitarra River Valley (ZRC-VRC) in Colombia. In this research, a multi-criteria approach (MCA) was applied to analyze the impact of ASGM. This analysis is based on the community environmental agreements to preserve CoS and CoH areas, the ecological importance of these areas, as well as the results of mercury dispersion in the Cimitarra river basin, with concentrations found 40 km downstream of the mining area of 0.09 µgTHg L−1 in the Cimitarra river, 0.07 µgTHg L−1 in the CoH, and 0.01 mgTHg kg−1 in the tissues of macrophytes, as well as the increase in deforestation since 2020 in the CoS, due to a 1.8% (990 ha) loss of forest cover, with 693 ha of the forest cover loss coinciding with areas related to the opening of new mines. The MCA showed that the main impact is found within the criterion Social and armed conflict, followed by Deforestation. This research offers recommendations to reduce impact scores, such as the implementation of a sustainable development plan (PDS) of the ZRC-VRC, and it highlights the urgent need to safeguard the community conservation areas.

Pollutants doi: 10.3390/pollutants4020017

Authors: Major Ballard Buddhi R. Gyawali Shikha Acharya Maheteme Gebremedhin George Antonious Jeffrey Scott Blakeman

Open burning poses a significant threat to human health and the environment by releasing hazardous chemicals and exacerbating plastic pollution. Urgent action is required to address its pervasive impact and the substantial release of gaseous pollutants. Limited research has explored the demographic aspect of open burning behavior, with none specifically conducted in Kentucky. An analysis of open burning complaints reported to the Kentucky Division for Air Quality in 2015, 2019, and 2021 revealed no significant differences in reported incidents by month and county. Binary logistic regression analyses identified the urban vs rural divide as significant predictors of open burning incidents, while violations were influenced by both urban and rural factors and average household income. Unemployment rates and the percentage of individuals with less than a high school diploma did not significantly predict open burning violations. Targeted interventions at the state and local level, focusing on rural areas and economically disadvantaged communities, can effectively address and mitigate open burning issues.

Pollutants doi: 10.3390/pollutants4020016

Authors: Nectaire Lié Nyamsi Tchatcho Paul Alain Nana Ernest Koji Siméon Tchakonté Yolande Elsa Lando Zangue Prospère Jeunemi Keu Geneviève Bricheux Télesphore Sime-Ngando

As bioindicators, benthic macroinvertebrates are often used to assess stream quality. Based on standard hydrobiological study techniques, the physicochemical and biological health status of the Missolé stream was assessed. Waters of the Missolé stream were found to be slightly acidic (pH: 6.23–6.26) and well-oxygenated (O2: 69.80–76.80%), with low values of temperature (T°: 23.60–24° C), turbidity (49.40–88.40 FTU) and mineralized ions (NH4+: 0–1.19 mg/L; NO2-: 0–1.61 mg/L; NO3-: 0.02–6.80 mg/L). Concerning aquatic invertebrate communities, a total of 489 individuals, grouped in two classes, eight orders and 35 families, all belonging to the phylum Arthropoda, were collected and identified. The class of Insecta was the most diversified, with seven orders and 32 families, while that of Crustacea had only one order and three families. Overall, Insecta accounted for 52.35% of the total abundance, and Decapod Crustacea was 47.65%. The three predominant families were Palaemonidae, Dytiscidae and Atyidae. Shannon and Weaver (H’) and Piélou’s evenness (J) indices were high at all stations and showed a slight decrease from upstream to downstream. In the same vein, the Hilsenhoff Biotic Index (HBI) classified the water quality of the Missolé stream as medium. Overall, this suburban aquatic ecosystem offers moderately favorable living conditions for aquatic biota.

Pollutants doi: 10.3390/pollutants4020015

Authors: Kalyani Prasad Bhagwat Denis Rodrigue Laura Romero-Zerón

The rapid increase in soil and water pollution is primarily attributed to anthropogenic factors, notably the mismanagement of post-consumer plastics on a global scale. This exploratory research design evaluated the effectiveness of natural hydrophobic cattail (Typha Latifolia) fibres (CFs) as bio-adsorbents of microplastic particles (MPPs) from wastewater. The study investigates how the composition of the adsorption environment affects the adsorption rate. Straightforward batch adsorption tests were conducted to evaluate the “spontaneous” sorption of MPPs onto CFs. Five MPP materials (PVC, PP, LDPE, HDPE, and Nylon 6) were evaluated. Industrial wastewater (PW) and Type II Distilled Water (DW) were employed as adsorption environments. The batch test results show that CFs are effective in removing five MPP materials from DW and PW. However, a higher removal percentage of MPPs was observed in PW, ranging from 89% to 100% for PVC, PP, LDPE, and HDPE, while the adsorption of Nylon 6 increased to 29.9%, a removal increase of 50%. These findings indicate that hydrophobic interactions drive the “spontaneous and instantaneous” adsorption process and that adjusting the adsorption environment can effectively enhance the MPP removal rate. This research highlights the significant role that bio-substrates can play in mitigating environmental pollution, serving as efficient, sustainable, non-toxic, biodegradable, low-cost, and reliable adsorbents for the removal of MPPs from wastewaters.

Pollutants doi: 10.3390/pollutants4020014

Authors: Sérgio Mateus Chilaule Xadreque Vitorino Macuacua Alfredo Pedro Mabica Nelson Alexandre Miranda Henrique dos Santos Pereira Eduardo Samo Gudo Tatiana Marrufo Santiago García-López Myriam Lopes

The impact of climate change has made weather events more extreme, unpredictable and frequent. In the last 4 years, Mozambique has been devastated by 8 major cyclones, resulting in material and human damage and affecting the functioning of basic local services, such as in the water and health sectors. In this study, we explored the environmental components of the climate–water quality–disease relationship that could drive the dynamics of waterborne diseases. Statistical models and geospatial information technologies (GITs) were used to analyse water quality and the relationship with waterborne diseases between 2016 and 2023. Results indicate that water quality is the main element, between precipitation natural disasters and waterborne diseases, on which a relevant public health intervention can act to ameliorate the future negative impacts of climate change and disease incidence. The results of this study also showed that the quality of water affected mainly by heavy rain events varies in different regions and in different seasons.

Pollutants doi: 10.3390/pollutants4020013

Authors: Abhijnan Bhat Kamna Ravi Furong Tian Baljit Singh

Arsenic (As) contamination is a serious global concern, polluting our natural resources, including water and soil, and posing a danger to the environment and public health. Arsenic is present in the groundwater of several countries and this contaminated water is used for irrigation, drinking, and food preparation, which poses the greatest threat to public health. Nearly 106 countries are affected by groundwater arsenic contamination and an estimated 230 million individuals worldwide are exposed to its adverse health effects, including increased cancer risks, associated cardiovascular disease and diabetes, skin lesions, neurological effects, kidney damage, and foetal or cognitive-development-related complications. Arsenic is highly toxic and ranked first in the priority list of ATSDR (Agency for Toxic Substances and Disease Registry, 2022) and among the 10 chemicals of major public health concern on the World Health Organization (WHO) list. The maximum permissible level of arsenic in drinking water has been established at 10 µg/L by WHO, as well as by the Environmental Protection Agency (EPA) and European Union (EU). These regulatory standards underscore the gravity of the problem, and actions to prioritise the development of effective detection, mitigation strategies, and collaborative initiatives are necessary. This opinion article covers (i) arsenic footprints—global scenario and impact, (ii) awareness and education and (iii) mitigation approaches (detection and removal strategies) and future perspectives, which collectively will help in controlling and preventing As contamination of our global water resources. Regulatory and legislative bodies and development agencies are crucial for raising awareness and countering this alarming concern by implementing collaborative actions to protect our environment and public health and to provide safe drinking water for all.

Pollutants doi: 10.3390/pollutants4020012

Authors: Qingyang Liu Yanju Liu

Biogenic volatile organic compounds (BVOCs) are responsible for the formation of ozone and secondary organic aerosols (SOAs). Our knowledge about how black carbon particles influence BVOC emissions from terrestrial ecosystems is limited; terrestrial vegetation captures black carbon particles as a sink. In this research, the BVOC emissions from the leaves of four terrestrial plants were measured using an RAE PGM-7300 BVOC analyzer. Then, the leaves from four types of trees were exposed to submicron carbon black for 24 h and 48 h in an ambient environment, respectively. Comparisons between the BVOC emissions before and after exposure to submicron carbon black were performed. Our results indicated that the emissions of BVOC from the leaves of four types of trees varied from 90 to 270 μg g−1 h−1 and depended on the species. The exposure to submicron black carbon particles had negligible impacts on the BVOC emissions from the leaves of four types of trees.

Pollutants doi: 10.3390/pollutants4020011

Authors: Omar Del Monte Alessandro Paola Bertin Pérez Laszlo Sajo-Bohus Daniel Palacios Fernández

Natural background gamma rays and their effects on human health are essential components of both radiation protection and public concern. In the frame of these aspects, the mapping of the natural gamma dose rate values of the Province of Asti is given. The Asti Fire Brigade Command approved a project relating to the mapping of gamma radiation from the natural background in the territory of Asti. The project engaged both the Nuclear, Biological, Chemical, and Radiological (NBCR) and Topography Applied to Rescue (TAS) components of the Asti Command. Skilled personnel, comprising level 1 TAS operators for data collection and level 2 TAS operators for cartographic analysis, were deployed across the six working days. The methodology involved the use of two digital handheld radiation G-M detectors, in conjunction with a portable GPS unit, including the Global Mapper software. One of the significant findings of this study is the observation that the natural gamma dose rate levels were 201.25% higher in the streets of the city center compared to other areas, predominantly because the building materials in these locations contain a higher amount of natural radionuclides. The results indicated that the level of natural gamma dose rates in the studied region is close to the global average value.

Pollutants doi: 10.3390/pollutants4010010

Authors: Isabela Brandolis Alves Falconi Melanie Mackay Geety Zafar Maria E. Holuszko

Plastic contamination is commonly reported in urban and rural soils, as well as in fresh and ocean waters. Canada’s government has attempted to limit the contamination of single-use plastic by banning the manufacturing and selling of specific types of plastic. In British Columbia, current regulations governing commercial composting state that when compost has less than 1% of its dry weight representing foreign materials (including plastic), it can be sold and used in soils. However, due to the low density of plastic and its potential to break down into microparticles, this amount may be enough to become toxic when used in agricultural soils. This paper studies contamination of plastic in garden soils and summarizes how this can affect the environment with a preliminary examination of a garden soil sample. The examination showed that the garden soil sample contained mainly low-density polyethylene, polyethylene and polypropylene plastics (identified through ATR-FTIR) in oxidized and unoxidized forms that can come from commercial composting and hypothesizes that this plastic could break down into microplastic particles. In order to limit the amount of plastic contamination in agricultural soils, it is necessary to modify current compost regulations in order to treat plastic differently than other foreign materials (glass, metal, wood).