Search Results (413)

South Dongting Lake is an essential aquatic ecosystem that receives substantial water inflows from the Xiangjiang and Zishui Rivers. However, it is significantly impacted by human activities, including mining, smelting, and farming. These activities have led to serious contamination of the lake’s sediments with heavy metals (HMs). This study investigated the distribution, mobility, and influencing factors of HMs at the sediment–water interface. To this end, sediment samples were analyzed from three key regions (Xiangjiang River estuary, Zishui River estuary, and northeastern South Dongting Lake) using traditional sampling methods and Diffusive Gradients in Thin Films (DGT) technology. Analysis of fifteen HMs (Pb, Bi, Ni, As, Se, Cd, Sb, Mn, Zn, V, Cr, Cu, Tl, Co, and Fe) revealed significant spatial heterogeneity. The results showed that Cr, Cu, Pb, Bi, Ni, As, Se, Cd, Sb, Mn, Zn, and Fe exhibited high variability (CV > 0.20), whereas V, Tl, and Co demonstrated stable concentrations (CV < 0.20). Concentrations were found to exceed background values of the upper continental crust of eastern China (UCC), Yangtze River sediments (YZ), and Dongting Lake sediments (DT), particularly at the Xiangjiang estuary (XE) and in the northeastern regions. Speciation analysis revealed that V, Cr, Cu, Ni, and As were predominantly found in the residual fraction (F4), while Pb and Co were concentrated in the oxidizable fraction (F3), Mn and Zn appeared primarily in the exchangeable fractions (F1 and F2), and Cd was notably dominant in the exchangeable fraction (F1), suggesting a high potential for mobility. Additionally, DGT results confirmed a significant potential for the release of Pb, Zn, and Cd. Contamination assessment using the Pollution Load Index (PLI) and Geoaccumulation Index (Igeo) identified Pb, Bi, Ni, As, Se, Cd, and Sb as major pollutants. Among these, Bi and Cd were found to pose the highest risks. Furthermore, the Risk Assessment Code (RAC) and the Potential Ecological Risk Index (PERI) highlighted Cd as the primary ecological risk contributor, especially in the XE. The study identified sediment grain size, pH, electrical conductivity, and nutrient levels as the primary influencing factors. The PMF modeling revealed HM sources as mixed smelting/natural inputs, agricultural activities, natural weathering, and mining/smelting operations, suggesting that remediation should prioritize Cd control in the XE with emphasis on external inputs. Full article

Barium chloride (BaCl₂), a known environmental pollutant, induces organ-specific oxidative stress through disruption of redox homeostasis. This study evaluated the protective effects and safety profile of sodium copper chlorophyllin (SCC) and ascorbic acid (ASC) against BaCl₂-induced oxidative damage in the liver and brain of mice using a two-phase experimental protocol. Animals received either SCC (40 mg/kg), ASC (160 mg/kg), or their combination for 14 days prior to BaCl₂ exposure (150 mg/L in drinking water for 7 days), allowing evaluation of both preventive and therapeutic effects. Toxicological and behavioral assessments confirmed the absence of systemic toxicity or neurobehavioral alterations following supplementation. Body weight, liver and kidney indices, and biochemical markers (Aspartate Aminotransferase (ASAT), Alanine Aminotransferase (ALAT), creatinine) remained within physiological ranges, and no anxiogenic or locomotor effects were observed. In the brain, BaCl₂ exposure significantly increased SOD (+49%), CAT (+66%), GPx (+24%), and GSH (+26%) compared to controls, reflecting a robust compensatory antioxidant response. Although lipid peroxidation (MDA) showed a non-significant increase, SCC, ASC, and their combination reduced MDA levels by 42%, 37%, and 55%, respectively. These treatments normalized antioxidant enzyme activities and GSH, indicating an effective neuroprotective effect. In contrast, the liver exhibited a different oxidative profile. BaCl₂ exposure increased MDA levels by 80% and GSH by 34%, with no activation of SOD, CAT, or GPx. Histological analysis revealed extensive hepatocellular necrosis, vacuolization, and inflammatory infiltration. SCC significantly reduced hepatic MDA by 39% and preserved tissue architecture, while ASC alone or combined with SCC exacerbated inflammation and depleted hepatic GSH by 71% and 78%, respectively, relative to BaCl₂-exposed controls. Collectively, these results highlight a differential, organ-specific response to BaCl₂-induced oxidative stress and the therapeutic potential of SCC and ASC. SCC emerged as a safer and more effective agent, particularly in hepatic protection, while both antioxidants demonstrated neuroprotective effects when used individually or in combination. Full article

Perfluorooctanoic acid (PFOA) and its replacement, GenX, are per- and polyfluoroalkyl substances (PFASs) widely used in industrial and consumer applications. Pregnant women are a vulnerable population to environmental pollutants. The maternal effects of GenX and PFOA exposure during pregnancy have not been fully elucidated. In this study, pregnant mice received daily oral doses of GenX (2 mg/kg/day), PFOA (1 mg/kg/day), or Milli-Q water (control) throughout gestation. Histopathological analyses revealed significant liver abnormalities in both exposure groups, including hepatocyte swelling, cellular disarray, eosinophilic degeneration, karyopyknosis, lipid vacuolation, and increased inflammatory responses. Through transcriptomics analyses, it was found that multiple metabolic and inflammatory pathways were enriched in both exposure groups. In the GenX group, overexpression of CYP4A, c-Myc, and Oatp2 proteins and decreased expression of EGFR and β-catenin in the liver suggested disruption of lipid and bile acid metabolism. In the PFOA group, significantly upregulated protein levels of NLRP3, GSDMD, caspase-1, IL-18, and IL-1β indicated hepatic pyroptosis. Despite these distinct pathways, both compounds triggered inflammatory cytokine release in the liver, consistent with the results of the transcriptomics analysis, suggesting shared mechanisms of inflammatory liver injury. Taken together, our findings provided novel insights into the hepatotoxicity mechanisms of GenX and PFOA exposure during pregnancy, underscoring the potential health risks associated with PFAS exposure. Full article

The hydrosystem composed of Lake Togo, Lagoon of Togoville, and Lagoon of Aného is located in the coastal zone of Togo and receives important and different kinds of mining waste that cause its degradation. This study aims to evaluate the physicochemical and metallic quality of these waters and determine the possible sources of these contaminants using geostatistical, multivariate, and special analysis methods. These waters were very mineralized according to the average conductivity (15.51 mS/cm). Average contents (μg/L) in trace elements varied from 2.46 μg/L for As to 141.63 μg/L for Pb. Average levels of Cd, Pb, Cr, and Ni were significantly higher than the WHO standards. Trace elements and physicochemical parameters showed strong spatial variations with the highest values recorded downstream of the hydrosystem. The main possible source of trace element pollution was the intrusion of seawater loaded with phosphate effluent, followed by atmospheric deposition and soil leaching. This hydrosystem, therefore, deserves special attention for better planning its management. Full article

Urban river ecosystems are increasingly threatened by anthropogenic activities, with wastewater discharge being a significant contributor. The complex nature and diverse sources of wastewater pose challenges in assessing its impact on water quality and ecological health. This study investigated the distribution, toxicity, and ecological effects of organic pollutants in an urban river system during the dry season. A comprehensive analysis was conducted of 16 phthalate esters (PAEs), 16 polycyclic aromatic hydrocarbons (PAHs), and 8 antibiotics, with a focus on several key pollutants. The results revealed distinct pollutant profiles: Dibutyl phthalate (DBP), Dimethyl phthalate (DEHP), and Diisobutyl phthalate (DIBP) were the predominant PAEs, while Chrysene was the most abundant PAH. Among antibiotics, Oxytetracycline and Norfloxacin were the dominant compounds. Wastewater treatment plant (WWTP) effluents significantly altered the composition of organic pollutants in receiving waters. Although dilution reduced the concentrations of some pollutants, certain organic compounds were detected for the first time downstream of the WWTP, and some specific compounds exhibited increased concentrations. Toxicity prediction using the Concentration Addition (CA) model identified DBP as the primary contributor to overall toxicity, accounting for the highest toxic load among all detected pollutants. Furthermore, WWTP effluents induced significant shifts in microbial community structure downstream, with incomplete recovery to upstream conditions. Integrated analysis of 16S rRNA gene sequencing, water quality assessment, and toxicity prediction elucidated the multifaceted impacts of pollution sources on aquatic ecosystems. This study provides critical insights into the composition, spatial distribution, and toxicity characteristics of organic pollutants in urban rivers, as well as their effects on bacterial community structure. The findings offer a scientific foundation for urban river water quality management and ecological protection strategies. Full article

Effluents from wastewater treatment plants (WWTPs) represent a potential pollution risk to surface waters. Moreover, the growing practice of using treated wastewater for irrigation has recently received increased attention in terms of its suitability, raising concerns about its impact on soil health, agricultural productivity, and human well-being. The aim of this study is to apply a comprehensive approach to assess the impact of wastewater from a Romanian WWTP on surface water quality and its suitability for irrigation practices. For this purpose, a set of physico-chemical parameters were analyzed, and a Water Quality Index (WQI) was developed based on Principal Component Analysis (PCA). The irrigation suitability of the effluent was further assessed using key parameters (electrical conductivity—EC; total dissolved solids—TDSs; turbidity; Biochemical Oxygen Demand—BOD₅) and specific irrigation indices (Sodium Adsorption Ratio—SAR; Permeability Index—PI; Residual Sodium Carbonate—RSC; Sodium percentage—%Na; Kelly’s ratio—KR). The results for the surface water quality indicated high contents of Na⁺ (10.2–42.5 mg/L), Cl⁻ (11.9–48.4 mg/L), and SO₄²⁻ (10.7–68.5 mg/L) downstream of the wastewater discharge point. The WQI, which reflects overall water quality for environmental health, showed excellent water quality, with a mean of 34 upstream and 47 downstream, suggesting the potential impact of treated wastewater discharge downstream. However, the irrigation indices revealed elevated sodium levels in the effluent, with %Na (up to 86%) categorizing 70% of the samples as unsuitable, while KR (up to 6.2) classified all samples as unsuitable. These findings suggest that despite a low impact on the river water, elevated sodium levels in effluent may limit suitability for irrigation, highlighting the importance of monitoring effluent water reuse. Full article

Shallow lakes are highly vulnerable to pollution due to their small water volume. Those that receive effluent from the drainfields of onsite wastewater treatment systems (septic tanks) may contain pharmaceuticals and personal care products (PPCPs) that escaped removal during treatment. This study examined the effects of seasonal rainfall variability on the assemblages and concentrations of fourteen PPCPs in two shallow lakes in West–Central Florida, USA: one surrounded by residents equipped with septic tanks and the other located within a nature preserve. Water samples were collected weekly during an 18-week interval from April to August 2021. Liquid chromatography–mass spectrometry analyses revealed the omnipresence of five PPCPs: theophylline, caffeine, cotinine, DEET, and testosterone, although acetaminophen, ibuprofen, and sulfamethoxazole were also common. Of all the PPCPs detected, theophylline, DEET, and acetaminophen concentrations were higher during the wet season in the septic tank-influenced lake, while caffeine, cotinine, and testosterone concentrations decreased. In the lake located in the nature preserve, theophylline, caffeine, and acetaminophen levels increased in the wet season. In contrast, cotinine, DEET, and testosterone levels decreased. Overall, more compounds were detected during the wet season, with highly hydrophobic PPCPs (fluoxetine, atorvastatin, and octocrylene) only present during this period. Full article

In regions with sustained air pollution, the adoption of protective health behaviors is critical, particularly among pregnant women—a population marked by physiological vulnerability and heightened receptivity to preventive guidance. Understanding and supporting patient-driven behavioral change requires attention to individual perception and awareness, which are shaped by socio-economic and spatial factors, as well as access to credible information. Objectives: This study investigates how pregnant women in Serbia perceive air quality, identifies determinants that influence these perceptions, and evaluates the extent and nature of behavioral adaptations undertaken to mitigate exposure-related risks. Methods: A cross-sectional survey was conducted among 279 pregnant women using a structured, researcher-administered questionnaire. Collected data included demographic and psychosocial variables, air quality perceptions, self-reported health effects, and behavioral responses. Residential proximity to land-use attributes was assessed using GIS-based spatial analysis. Results: Most participants perceived air quality as poor (68.8%), primarily informed by unofficial sources such as mobile applications and social media. Living close to continuous urban fabric (OR = 0.180, 95% CI: 0.059–0.558, p = 0.003) and water (OR = 0.306, 95% CI: 0.127–0.738, p = 0.008) was associated with poorer perceptions, while proximity to forests (OR = 2.938, 95% CI: 1.323–6.525, p = 0.008) correlated with more favorable assessments. Despite prevalent concern, around half of respondents (50.2%) reported no behavioral modifications. Importantly, none had received guidance from healthcare professionals on the topic. Conclusions: These findings highlight critical gaps in environmental health literacy and provider engagement. Integrating tailored communication and behavioral support in existing prenatal counseling could advance health-related quality of life in this vulnerable population. Full article

This article examines the impact of a new technical assistance (TA) and recognition program (BetterBev) on Massachusetts craft breweries’ adoption of pollution prevention/sustainability practices. The authors explore the following questions: How do technical assistance and recognition address the key barriers and promote P2/sustainability adoption? What are the outcomes and impacts of the implemented P2 practices? What specific P2/sustainability practices are most likely and least likely to be adopted by craft breweries receiving TA, and why? This study is based on 29 craft breweries in Massachusetts, U.S. Data was collected between November 2022 and March 2025 and included site visits; interviews with owners, founders, and head brewers; online research; and assessments of eight impact categories. This study found that providing TA was highly effective in encouraging participants to adopt new P2/sustainability practices (the 29 participants adopted 60 new P2/sustainability practices over two years). The TA helped overcome the main sustainability barriers for craft breweries—the lack of resources, time, and knowledge about available opportunities. MA breweries adopted most of their P2 practices in energy and CO₂ reduction, and the least in water and wastewater reduction. This study confirmed the importance of environmental information as a powerful driver for adopting P2/sustainability actions. Future initiatives should consider a train-the-trainer approach for scaling up P2/sustainability practices, where early adopters share their knowledge and experience with peers. Full article

This study evaluated the pollutant removal efficiency of two decentralized wastewater treatment plants (WWTPs) located in the high-altitude southern Andes of Ecuador, Acchayacu and Churuguzo, from 2015 to 2024. Acchayacu previously operated using an upflow anaerobic filter (UAF), and from 2021, it transitioned to using vertical-subsurface-flow constructed wetlands (VSSF-CWs). In contrast, Churuguzo employs surface-flow constructed wetlands (SF-CWs). These systems were assessed based on parameters such as the five-day biochemical oxygen demand (BOD₅), chemical oxygen demand (COD), total phosphorus, organic nitrogen, ammonia nitrogen, total solids, fecal coliforms (TTCs), and total coliforms (TCs). The data were divided into two subperiods to account for the change in technology in Acchayacu. Statistical analysis was conducted to determine whether significant differences existed between the treatment efficiencies of these technologies, and the SF-CW was found to consistently outperform both the UAF and VSSF-CW in removing organic matter and microbial pollutants. This difference is likely attributed to the longer hydraulic retention time, lower hydraulic loading rate, and vegetation type. The findings highlight the environmental implications of treatment technology selection in WWTPs, particularly regarding the quality of receiving water bodies and their potential applications for public health, proper water resource management, and the design of decentralized systems in high-altitude regions, especially in developing countries. Full article

Synthetic dyes are commonly present in industrial wastewater and when discharged in water bodies without receiving a treatment capable of removing or destroying them, they turn into concerning water pollutants. These organic contaminants threaten living beings due to their toxicity, and some of them can even damage DNA. Consequently, in order to achieve sustainable development, it is necessary to develop eco-friendly tools that can efficiently manage this kind of pollution. In the present study the aqueous extract from the leaves of Leucaena leucocephala (an invasive plant species native to Mexico) was used to produce green nano zero-valent iron (nZVI). The nanomaterial was characterized (TEM, UV–vis, FTIR, SEM, EDS, XRD) and assayed regarding its antioxidant potential (DPPH test) and capacity to remediate the pollution caused by two dyes. It proved to be able to adsorb nigrosine (288.30 mg/g of nanomaterial) and tartrazine (342.50 mg/g of nanomaterial), and also displayed antioxidant activity (effective concentration to discolor 50% of the DPPH solution = 286.02 μg/mL). Therefore, the biogenic antioxidant nanoparticle proved also to be a possible nanotool to be applied to remediate water contamination caused by these synthetic dyes. Full article

Abandoned pits and quarries in Ontario, Canada, are on the rise due to industrialization, leading to ecosystem disruption and soil contamination with pollutants such as cadmium, cobalt, nickel, and barium, which may leach into nearby water systems. Current rehabilitation processes are slow to initiate, and therefore, the site remains in a contaminated condition for years. Phytoremediation, which involves using plants to remove contaminants from soils, is receiving increased attention for cleaning up decommissioned mines. This type of rehabilitation is normally practiced in situ by hand-planted and managed vegetation chosen for the specific purpose of contaminant removal. This study investigated the phytoremediation potential of indigenous plants as local seed sources to rehabilitate decommissioned quarries in Ontario. This study also investigated the potential of native plants to naturalize in the disturbed areas, thus providing a natural clean-up of the contaminants. Thus, if successful, this process will also initiate the re-establishment of native wildlife in the area. Through a literature review, 74 plant species were identified as capable of remediating 20 contaminants often found on the decommissioned quarry sites. The results may help ecosystem managers to adopt environmentally sustainable strategies to clean up contaminated sites such as decommissioned mines and quarry areas. Full article

Freshwater bivalves play essential ecological roles in ecosystems, but they are among the most threatened fauna worldwide. Despite receiving industrial and domestic wastes, the Guandu River is the main source of drinking water for more than nine million people in the Rio de Janeiro metropolitan region. This study aimed to assess how infaunal bivalves respond to water and sediment quality in the Guandu River basin. Samples were collected at 10 sites across reservoirs, lotic, and lentic systems during cold–dry and warm–rainy seasons. Four bivalves were identified: Anodontites trapesialis, Diplodon ellipticus, Corbicula fluminea (non-native), and C. largillierti (non-native). Native species were restricted to two lentic sites at Guandu Lagoon, with the poorest environmental quality, significantly affected by high chlorophyll a and ammonia in the water. In contrast, C. fluminea was widely distributed and more abundant in the basin but restricted to less degraded sites, suggesting a lower tolerance to environmental pollution. Multivariate analyses indicated significant differences in environmental conditions and species–environment correlation. The non-native species spread and poor environmental quality threaten native bivalves in the Guandu River basin, leading them to a local extinction risk. Results highlight the need for effective management and conservation actions to protect biodiversity in tropical river basins. Full article

The primary sources of widespread pollution in most river catchments are improperly treated final effluents from various wastewater treatment plants (WWTPs), affecting the physicochemical characteristics of the receiving water bodies. Wastewater discharge must be monitored regularly to ensure compliance with national and municipal water quality regulatory/standard restrictions. This study monitored the physicochemical parameters of two typical WWTPs (WWTP A = a peri-urban plant and WWTP B = a rural plant) for 5 months. The physicochemical parameters that were assessed included pH, temperature, total dissolved solids (TDSs), turbidity, chemical oxygen demand (COD), alkalinity, dissolved oxygen (DO), free chlorine, chloride, sulphate, phosphate, ammonium, and electrical conductivity (EC). The evaluation yielded the following results: temperature (14 to 21 °C and 14 to 23 °C), pH (7.2–8.2 and 7.3–8.4), EC (90–800 μs/cm and 80–750 μs/cm), TDSs (65–440 and 55–410 mg/L), alkalinity (2.6–20.9 mg/L), nitrate (0.24–26.5 mg/L), nitrite (0.01–90 mg/L), phosphate (0.0–18.0 mg/L and 0.0–21 mg/L), ammonia (0.2–75 mg/L and 0.8–70 mg/L), sulphate (0.0–18.0 mg/L and 0.0–21 mg/L), chloride (5.0–22.0 mg/L and 2.0–25 mg/L), COD (6.0–710 mg/L and 7.0–800 mg/L), and turbidity (0.4–150 NTU and 1.8–130 NTU) for wastewater treatment A and B, respectively. The results also showed that temperature, pH, TDSs, nitrite/nitrate, chloride, turbidity, alkalinity, sulphate, and free chlorine were among the parameters in the final effluent discharged that met the set guidelines. In contrast, parameters such as COD, EC, phosphate, and ammonia did not meet the guideline values for most of the sampling period for both WWTPs. Furthermore, this study found that WWTPs reduced nitrate, sulphate, phosphate, and COD pollutants by more than 90% while maintaining 60% alkalinity. Temperature, pH, TDSs, EC, Cl⁻, and other parameters were less than 40% for WWTP A and roughly less than 50% for WWTP B. Full article