Pollutants, Volume 5, Issue 4 (December 2025) – 11 articles

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. Full article

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. Full article

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. Full article

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. Full article

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. Full article

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), PM_2.5, 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 PM_2.5 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, PM_2.5, 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. Full article

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 PM_2.5 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. Full article

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 PM_2.5 for one year. Descriptive statistics were used to describe study participant characteristics and health status. Mean indoor averages, median PM_2.5 measurements, and two-tailed tests were used to assess differences in concentrations of PM_2.5. 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 PM_2.5 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 PM_2.5 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. Full article

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. Full article

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. Full article