This study presents a longitudinal, integrative assessment of contamination in the Jaguaribe River estuary (Cear & aacute;, Brazil) following the 2019 oil spill, combining chemical, biological, toxicological, and community-engaged approaches. Polycyclic aromatic hydrocarbons (PAHs) and trace elements were quantified in Mytella strigata, alongside physicochemical parameters and genotoxic biomarkers. Total PAHs (& sum;36PAH) ranged from 29.1 to 88.8 mu g/kg wet weight, with molecular distributions indicating a mixed-source profile characterized by a weathered petrogenic signature and episodic pyrogenic inputs. Temporal variability suggested dynamic contamination driven by remobilization and seasonal processes. Despite detectable petroleum-derived compounds, PAHs contributed minimally to human health risk (CR <= 1 & times; 10-5). In contrast, trace elements - particularly arsenic and nickel - were the primary drivers of toxicological concern (CR = 1 & times; 10-3). Although concentrations were generally within regulatory limits, risk assessment indicated low non-carcinogenic but elevated carcinogenic risk, especially under high seafood consumption scenarios typical of local shellfish gatherers. Community-engaged research revealed persistent concerns regarding food safety and institutional response, reflecting awareness of cumulative exposure risks and socio-environmental vulnerability. Overall, this study demonstrates that even low contaminant levels can result in significant health risks when combined with chronic exposure. These findings highlight the need for long-term, multidisciplinary monitoring and context-specific regulatory strategies to protect vulnerable coastal populations.
Tea plantations represent a relatively stable ecosystem, yet improper pesticide use poses significant risks to human and environmental health. This study aimed to assess the risks of major insecticides registered for use in tea plantations to honeybees and non-target arthropods (NTAs). A list of registered active ingredients was compiled, and 11 representative insecticides were selected for primary risk assessment. Data on insecticide use strategies including dosage, number of applications, and application method, along with ecotoxicological characteristics, were collected to calculate predicted exposure concentrations (PEC), predicted no-effect concentrations (PNEC), and acute risk quotients (RQ = PEC/PNEC). For honeybees, only chlorantraniliprole and afidopyropen posed an acceptable risk (RQ <= 1). In contrast, the RQ values for bifenthrin, imidacloprid, clothianidin, malathion and abamectin were 101-585 times higher than acceptable levels. For NTAs, only diafenthiuron, chlorantraniliprole, tolfenpyrad, and afidopyropen posed acceptable risks; while the majority of other insecticides including lambda-cyhalothrin, bifenthrin, imidacloprid, clothianidin, and malathion, exhibited moderate to high risks. These findings indicate that the use of high-risk pesticides in tea plantations should be restricted or phased out. In the interim, adopting mitigation strategies like chemical substitution with low-risk alternatives, optimized application timing, and integrated pest management (IPM) is crucial to protect honeybees, NTAs, and the broader ecosystem.
Heavy metal pollution in traditional handicraft sites has been a significant concern due to its environmental, ecological, and health impacts. This study investigated the accumulation of heavy metals, including As, Cd, Cr, Cu, Zn, Ni, Mn, and Pb in ten cultivated crop species, associated garden and paddy soils, together with related health risks. Heavy metals in 64 crop samples, including rice and leafy vegetables, were analyzed using the ICP-OES. Heavy metal concentrations in ten crops (mg/kg, fresh weight) varied within 0.01-0.09 (As), 0.004-0.01 (Cd), 0.54-2.17 (Cu), 0.04-0.25 (Cr), 2.94-17.2 (Mn), 0.02-0.33 (Ni), 0.002-0.02 (Pb), and 2.62-46.3 (Zn). Although the concentrations of heavy metals in all studied crops were within the thresholds by the European Union, FAO/WHO, and Chinese Ministry of Health, high non-cancer (hazard index, HI = 3.49 for adults and 5.18 for children) and cancer (incremental lifetime cancer risk, ILCR = 1.19 & times;10(-3) for adults and 3.58 & times;10(-4) for children) risks to the exposed community were found. Rice contributes 93.2-94.5% of the total HI and 92.2-94.7% of the total ILCR. Effective remediation of metal-contaminated soils, and careful crop selection or application of amendments were proposed to mitigate these risks.
The excessive eutrophication of surface water will lead to the imbalance of species distribution in water ecosystem, and destroy the flow of material and energy in the system. Detection results of surface water in the Jianghan-Dongting Plain showed that the median concentration of TN was more than 1.60 mg/L, with the excess rate over 60.0%. The TP concentration was not high and the excess rate was less than 10.0% except for Qianjiang. The optimal nitrogen and phosphorus requirements for algae growth in the study area were 1.20 mg/L and 0.07 mg/L respectively, with the most suitable N/P ratio ranging around 16:1. Phosphorus was considered as the limiting factor when N/P exceeded 30:1. Nitrogen was considered as the limiting factor when N/P was less than 10:1. The findings indicated that the plain area between the Yangtze River and the Han River was a high-risk zone, while the southern region of the Yangtze River exhibited the lowest risk of water environment eutrophication. In addition, the risk of eutrophication of water environment was greatly affected by human activities. The findings of this study directly contributed to improving the water ecological security system of the Jianghan-Dongting Plain and provided scientific support for the risk management.
Inrush of acidic mine water from abandoned coal mines poses serious threat to groundwater environment by mobilizing heavy metals and lowering pH, thereby endangering ecosystems and human health. In this study, inrush water samples from nine abandoned coal mines in Wangcang, Sichuan, China, were analyzed for eight heavy metals (Cr(VI), Fe, Mn, Hg, As, Zn, Pb, and Cd) using inductively coupled plasma-mass spectrometry (ICP-MS). The ecological risk was assessed through species sensitivity distribution (SSD) based on native aquatic species data, while health risks were evaluated using USEPA exposure models. Results showed that the mine water was acidic (pH 1.6-7.1) with high metal concentrations, particularly Fe, Zn, Mn, and Cd, with mean values of 1048, 11.5, 4.6, and 0.49 mg/L, respectively, exceeding the Chinese Class III groundwater quality standards. The SSD-derived hazardous concentration for 5% of species (HC5) values ranged from 7.08 & times; 103 mu g/L (Hg) to 3.09 & times; 10(5) mu g/L (Pb), indicating that aquatic species were more sensitive to Hg than Pb. Risk quotients (RQs) revealed Fe as the dominant ecological risk factor across all sites. Although non-carcinogenic hazard indices (HIs) remained below 1, carcinogenic risk from Cr(VI), Cd, and As exceeded the 1 & times; 10(-4) threshold, with oral ingestion identified as the primary exposure pathway. The findings indicate substantial ecological and health risks from abandoned mine inflows, warranting targeted remediation of Fe and carcinogenic metals.
This study conducted a probabilistic health risk assessment of representative heavy metals (Pb, Cd, Hg) using nationally representative secondary datasets on dietary intake, environmental media (air, soil, indoor dust), and smoking exposure, combined with literature-based exposure factors. Dietary intake was the dominant exposure pathway, with agricultural foods contributing most to Pb exposure and seafood dominating Cd and Hg exposure, while smoking was the major non-dietary contributor. Exceedance of the acceptable TCR for Pb was observed in 0.51% of the 0-2 age group and in adult sub-populations (10.55-14.01%). In contrast, Cd TCR exceeded the acceptable limit across all sub-populations. For Hg, HI exceeded 1 in 3.21% of the 0-2 age group. Risk contribution analysis showed Pb exposure was associated with agricultural foods (13.17-15.79%) and smoking (13.14-19.09%), while Cd exposure was largely driven by seafood consumption (65.03-72.47%). Hg exposure was primarily attributed to seafood consumption (32.61-36.82%). Findings suggest prioritizing reduction of Cd exposure from food, controlling Pb exposure from air, minimizing soil and indoor dust ingestion in children, and reducing smoking-related exposure in adults.
This study evaluated exposure to per- and polyfluoroalkyl substances (PFAS) through routine dietary and tap water intake among residents of Downtown Augusta (GA, USA) in the Central Savannah River Area. Using community-based participatory research methods, we recruited 18 households (63 participants) and collected detailed grocery records, dietary intake data, and unfiltered residential tap water samples. Dietary PFAS exposure was modeled using national-level concentration data from the U.S. Food and Drug Administration, while drinking water samples were analyzed for targeted PFAS compounds. Monte Carlo simulations were employed to estimate individual intake rates, incorporating variability in contaminant levels, ingestion behavior, and body weight. Results showed that 33.3% of households exceeded the U.S. Environmental Protection Agency's (EPA) Maximum Contaminant Levels for PFOA and PFOS in tap water. Simulated intake estimates indicated that 100% of participants exceeded the EPA's draft reference dose (RfD) for PFOA, and 92.4% exceeded the RfD for PFOS. Although households provided food samples, these were not analyzed due to funding limitations. Sociodemographic analyses revealed that households with lower income and educational attainment experienced greater exposure risk. These findings highlight a disproportionate PFAS burden in underserved communities and reinforce the need for targeted mitigation strategies. The integration of environmental sampling, exposure modeling, and community engagement provides a replicable framework for identifying at-risk populations and informing equitable environmental health policies.
Climate change has been increasing over the past century and is projected to worsen further in the future in India. It has shown extreme negative impacts on agriculture, allied sectors, and vulnerable groups in society, especially in the Trans-Gangetic plain region of the country. Research evidence indicates that women in this region are more vulnerable to climate change than their male counterparts. Therefore, the present study aims to map hotspots using Gender-based Socio-climatic Vulnerability scores by applying Global Moran's I and Getis Ord Gi* tools in ArcGIS software using suitable indicators categorized under the dimensions of exposure, sensitivity, and adaptive capacity to measure gender inequality, discrimination against women, and socio-climatic vulnerability at the district level in Haryana. The findings revealed that Sirsa, Palwal, Mewat, Mahendragarh, Jind, and Fatehabad districts had higher levels of Gender-based Socio-Climatic Vulnerability, with Sirsa emerging as a Gender-based Socio-climatically vulnerable hotspot. The study introduces a novel spatial framework that explicitly links gender inequality with climate vulnerability, offering a new perspective for regional climate assessments. The findings provide critical insights for integrating gender perspectives into climate adaptation planning, emphasizing the need for targeted interventions to enhance women's resilience and protect livelihoods in climatically vulnerable farming communities, aligning with Sustainable Development Goals 5 (Gender equality) and 13 (Climate Action). Building on these insights, the study further underscores the need for gender-specific adaptation policies that strengthen women's access to resources and services, promote women-friendly technologies, support farm women through social protection measures, encourage livelihood diversification and targeted capacity building, and facilitate women's participation in local climate action planning and inclusion in cooperatives and self-help networks.
Methyl siloxanes (MSs) have adverse effects and are widespread in the environment. However, limited information on MSs in urban soil is available. This study collected 182 urban soil samples from Xi'an, Lanzhou, and Urumqi in Northwest China, and analyzed 15 MSs including 3 cyclic (D4-D6) and 12 linear (L5-L16) MSs in these samples for their occurrences, sources, and corresponding exposure risks. The total concentration of 15 MSs (Sigma(15)MSs) presented Urumqi (645 ng/g) > Xi'an (408 ng/g) > Lanzhou (346 ng/g). Linear MSs were dominant in Urumqi and Lanzhou, while cyclic MSs (CMSs) were predominant in Xi'an. Elevated Sigma(15)MSs were found in the west of Xi'an, the southern and northeastern of Urumqi, and the east of Lanzhou. MSs originated primarily from industrial emissions (38.5%) in Xi'an, siloxanes-containing product uses (48.5%) in Urumqi, and industrial/domestic product emissions (40.8%) in Lanzhou. The total average daily dose of children, adolescents, youths, and adults exposed to 15 MSs was 0.821-0.876, 0.654-0.698, 0.338-0.362, and 0.331-0.353 ng/kg/day, respectively. The overall exposure risk of two CMSs (i.e., D4 and D5) was low, however, the risk of MSs might be underestimated as the chronic reference doses of other MSs were unknown.
This study aimed to evaluate contamination levels, potential sources, and associated ecological and human health risks of metal(loid)s in surface water surrounding a municipal solid waste landfill and adjacent agricultural areas under a worst-case exposure scenario. The results indicated that during the pre-monsoon season, mean metal(loid) concentrations followed the order manganese > iron > copper > arsenic > nickel > lead > cadmium, whereas during the monsoon season the order was iron > manganese > nickel > arsenic > copper > lead > cadmium. Notably, arsenic concentrations in both seasons and manganese concentrations during the monsoon season exceeded Thai surface water quality standards for domestic and human use, as well as the Australian Drinking Water Guidelines. Source apportionment analysis identified contributions from landfill leachate, agricultural activities, and naturally occurring geochemical sources. Screening-level ecological risk assessment under a worst-case exposure scenario revealed that all metal(loid)s, except Pb, in both the pre-monsoon and monsoon seasons exceeded the threshold for adverse ecological effects. Screening-level human health risk assessment under a worst-case exposure scenario indicated cumulative non-carcinogenic and carcinogenic risks associated with multi-element exposure for both children and adults across both seasons, resulting from exceedances of health risk-based screening benchmarks when long-term exposure to season-specific concentrations was assumed. These findings highlight screening-level concerns for populations relying on surface water resources and underscore the need for further site-specific investigations and improved management of agrochemical use and municipal solid waste landfills to protect surface water quality.
The consumption of cetacean meat by humans persists in several regions worldwide, either legally or as part of long-standing cultural traditions. While health risks associated with mercury and polychlorinated biphenyls in marine mammals are well documented, less attention has been paid to per- and polyfluoroalkyl substances (PFAS). PFAS are persistent, bioaccumulative contaminants with well-established adverse effects on human health, and recent evidence indicates pronounced biomagnification in marine food webs. Cetaceans, as long-lived apex predators, can accumulate exceptionally high PFAS concentrations, particularly in liver, blood, and muscle tissues consumed by humans. Here, we synthesize recent data on PFAS levels in whales and dolphins and discuss the implications for human dietary exposure. Simple exposure scenarios suggest that even a single meal of cetacean meat may exceed current health-based guidance values by orders of magnitude. We argue that PFAS contamination adds a critical dimension to the human health risks associated with cetacean consumption, warranting renewed public health attention and precautionary guidance.
BTEX compounds (benzene, toluene, ethylbenzene, and xylene) are volatile organic chemicals that threaten air quality in paint-related workplaces and pose significant health risks, including carcinogenic effects from benzene. Occupational health regulations worldwide set legislative limit values for BTEX compounds, and most also require or recommend workplace risk assessments where hazardous exposures may occur. This study evaluates BTEX limit values established by the EU, OSHA, and NIOSH. Cancer and non-cancer risks associated with these limits are quantified using the U.S. EPA health risk assessment framework and compared with commonly accepted target risk levels. A benzene-specific physiologically based pharmacokinetic (PBPK) model is used to simulate internal benzene burdens under scenarios including reduced air concentrations, shortened work shifts, and fewer workdays. Findings indicate that current legislative limits, including recently updated EU values, lead to cancer and non-cancer risks that exceed commonly accepted target levels. PBPK simulations further show that reducing workdays or shift duration alone is insufficient to lower risks to acceptable levels; decreasing workplace BTEX concentrations is essential and should be complemented by shorter shifts and fewer workdays. Overall, the study underscores the importance of context-specific risk assessment and highlights the value of integrating PBPK modeling with traditional health risk assessment approaches.
