Human exposure risks for metals in soil near a coal-fired power-generating plant

Potentially Toxic Elemental Dispersion from the Brick Kilns: Preliminary Exploration of Mechanistic Pathways

This study investigates the contamination status and dispersion of 11 potentially toxic elements by exploring the potential mechanistic pathways by analyzing 60 samples (coal, ash, topsoil, and subsoil) from and around the coal-based brick kilns by neutron activation analysis. The meann=10 concentrations (μg g-1) of scandium (Sc: 3.85), zinc (Zn: 79.21), Antimony (Sb: 4.06), and cesium (Cs: 4.81) in coal samples and manganese (Mn: 488), antimony (Sb: 10.9), and cesium (Cs: 20.3) in ash samples were 2.8-4.3 times and 1.1-2.5 times higher than world average values, respectively. In soil samples, averagen=40 abundances (μg g-1) of chromium (Cr: 109), zinc (Zn: 144), arsenic (As: 8.98), rubidium (Rb: 113), antimony (Sb: 2.29), and cesium (Cs: 14.3) are 1.1-5.7 times higher than the crustal values. Additionally, geo-environmental indices showed that cesium (Cs) and chromium (Cr) had undergone severe modification relative to the crustal value, and the corresponding soil samples were moderately contaminated. The positive matrix factorization (PMF) model reveals that aerodynamic transportation contributes 22% to the elemental transportation of manganese, titanium, and iron throughout the soil profile in distant soil. In comparison, hydrodynamic transportation contributes 25% for As, Zn, and Sc in both topsoil and subsoil in the nearby soil. However, the combined process of bio-geo-accumulation, hydrodynamic leaching, and aerodynamic convection mechanisms contributes 53% of the dispersion and distribution of cesium (Cs), cobalt (Co), rubidium (Rb), and chromium (Cr) in the ambient pedosphere around the brick kilns which local geology, soil properties, solubility, and weathering can further influence. Our research findings contribute to advancing scientific approaches for investigating soil contamination, including the mechanistic pathways of potentially toxic elements and the risks associated with brick kilns.

Ecological and health risk assessments of heavy metal contamination in soils surrounding a coal power plant

Coal combustion at power plants is a significant source of environmental pollution, with the deposition of heavy metals in soils leading to extensive ecosystem contamination and exacerbating the harmful impacts of human activities. This study presents a field investigation of heavy metal concentrations in soils around a coal-fired power plant, with monitoring sites located 1.7 to 15.2 km from the plant. Data collection occurred in 2015, 2020, and 2024 across 11 monitoring sites. X-ray fluorescence analysis was used to assess heavy metal concentrations in soil. A life cycle assessment (LCA) with ReCiPe method was conducted to evaluate the impacts on both ecological and human health. The results revealed that the concentrations of Pb, Zn, Cu, Ni, Mn, Cd, and Cr exceeded threshold levels set by both the World Soil Average and the Regional Geochemical Background. The correlation analysis shows that organic matter and clay content play vital roles in reducing the mobility of heavy metals in soil through adsorption. Notably, strong correlations between Pb and Cd suggest a common origin from coal seam minerals. The LCA shows that freshwater ecotoxicity, marine ecotoxicity, terrestrial ecotoxicity, and human toxicity increased by over 30 % compared to the World Soil Average pollutant levels. Nickel was identified as the primary contributor to marine and freshwater ecotoxicity, while manganese had the most significant impact on human toxicity. This study provides a better understanding of the long-term consequences of heavy metal accumulation in soils near coal-fired power plant. The data on anthropogenic impacts are crucial for developing effective strategies to mitigate environmental risks associated with pollution.

Tampons as a source of exposure to metal(loid)s

BACKGROUND

Between 52-86% of people who menstruate in the United States use tampons-cotton and/or rayon/viscose 'plugs'-to absorb menstrual blood in the vagina. Tampons may contain metals from agricultural or manufacturing processes, which could be absorbed by the vagina's highly absorptive tissue, resulting in systemic exposure. To our knowledge, no previous studies have measured metals in tampons.

OBJECTIVES

We evaluated the concentrations of 16 metal(loid)s in 30 tampons from 14 tampon brands and 18 product lines and compared the concentrations by tampon characteristics.

METHODS

About 0.2 - 0.3 g from each tampon (n = 60 samples) were microwave-acid digested and analyzed by inductively coupled plasma mass spectrometry (ICP-MS) to determine concentrations of arsenic, barium, calcium, cadmium, cobalt, chromium, copper, iron, manganese, mercury, nickel, lead, selenium, strontium, vanadium, and zinc. We compared concentrations by several tampon characteristics (region of purchase, organic material, brand type) using median quantile mixed models.

RESULTS

We found measurable concentrations of all 16 metals assessed. We detected concentrations of several toxic metals, including elevated mean concentrations of lead (geometric mean [GM] = 120 ng/g), cadmium (GM = 6.74 ng/g), and arsenic (GM = 2.56 ng/g). Metal concentrations differed by region of tampon purchase (US versus European Union/United Kingdom), by organic versus non-organic material, and for store- versus name-brand tampons. Most metals differed by organic status; lead concentrations were higher in non-organic tampons while arsenic was higher in organic tampons. No categoriy had consistently lower concentrations of all or most metals.

DISCUSSION

Tampon use is a potential source of metal exposure. We detected all 16 metals in at least one sampled tampon, including some toxic metals like lead that has no "safe" exposure level. Future research is needed to replicate our findings and determine whether metals can leach out of tampons and cross the vaginal epithelium into systemic circulation.

Bibliometric analysis on mercury emissions from coal-fired power plants: a systematic review and future prospect

Coal-fired power plants (CFPPs) are one of the most significant sources of mercury (Hg) emissions certified by the Minamata Convention, which has attracted much attention in recent years. In this study, we used the Web of Science and CiteSpace to analyze the knowledge structure of this field from 2000 to 2022 and then reviewed it systematically. The field of Hg emissions from coal-fired power plants has developed steadily. The research hotspots can be divided into three categories: (1) emission characterization research focused on speciation changes and emission calculations; (2) emission control research focused on control technologies; (3) environmental impact research focused on environmental pollution and health risk. In conclusion, using an oxygen-rich atmosphere for combustion and installing high-efficiency air pollution control devices (APCDs) helped to reduce the formation of Hg0. The average Hg removal rates of APCDs and modified adsorbents after ultra-low emission retrofit were distributed in the range of 82-93% and 41-100%, respectively. The risk level of Hg in combustion by-products was highest in desulfurization sludge (RAC > 10%) followed by fly ash (10% < RAC < 30%) and desulfurization gypsum (1% < RAC < 10%). Additionally, we found that the implementation of pollution and carbon reduction policies in China had reduced Hg emissions from CFPPs by 45% from 2007 to 2015, increased the efficiency of Hg removal from APCDs to a maximum of 96%, and reduced global transport and health risk of atmospheric Hg. The results conjunctively achieved by CiteSpace, and the literature review will enhance understanding of CFPP Hg emission research and provide new perspectives for future research.

Environmental impacts of Indian coal thermal power plants and associated human health risk to the nearby residential communities: A potential review

Worldwide, harmful emissions from coal power plants cause many illnesses contribute to premature deaths burden. Despite its high impact on human health and being a major source of toxic pollutants, coal has been considered a component of global energy for decades. Hence, this work was envisaged to understand the rising environmental and multiple health issues from coal power plants. Studies on the adverse impacts of coal power plants on the environment, including soil, surface water, groundwater and air, were critically evaluated. The health risk from exposure to different pollutants and toxic metals released from the power plant was also demonstrated. The study also highlighted the government initiatives and policies regarding coal power operation and generation. Lastly, the study focused on guiding coal power plant owners and policymakers in identifying the essential cues for the risk assessment and management. The current study found an association between environmental and human health risks due to power generation, which needs intervention from the scientific and medical fields to jointly address public concerns. It is also suggested that future research should concentrate on exposure assessment techniques by integrating source-identification and geographic information systems to assess the health effects of different contaminants from power plants and to mitigate their adverse impact.

Effects of atmospheric dust particles on common medicinal plants in an industrial area of West Bengal, India

The exposure of atmospheric dust particles on four common medicinal plants (Ocimum sanctum, Andrographis paniculata, Catharanthus roseous, and Kaempferia galanga, which are available in the study area and cultivated by the local people for medicinal purposes) affects their growth, levels of essential biochemical constituents and heavy metal concentration. The plant species were grown by pot cultivation in an industrial area with high levels of coal dust to assess the capacity of heavy metals accumulation in their leaves and changes in allometry and biochemical parameters. The results showed that annual average SPM and dustfall varied between 195.88 to 645.97 μg/m3 and 17.55 to 41.16 g/m2/month, respectively. Dustfall at different polluted sites was 2.4, 2.1, 1.5, 1.4, and 2.3 times higher than at the control site. The most prevalent heavy metal in atmospheric particulate matter was Zn, followed by Pb, Ni, Cu, Co, and Cd. Plant allometry measurements such as height, stem width, root length, petiole length, and leaf area are shown to have a strong and significant (p<0.05) negative correlation with dustfall and SPM. Total chlorophyll and RWC were inversely proportional to the dust load present in all the species. Except for Andrographis paniculata, chlorophyll and leaf-extracted pH of plant species were moderately correlated with APTI, whereas no correlation was noticed for ascorbic acid. A positive correlation between SPM and heavy metals in leaves was observed. The results implied that the cultivation and collection of medicinal plants from the study area could be potentially toxic to human health.

Determination of potential sources of heavy metals in patients with urothelial carcinoma in central Taiwan: a biomonitoring case-control study

The clarification of possible exposure sources of multiple metals to identify associations between metal doses and urothelial carcinoma (UC) risk is currently limited in the literature. We sought to identify the exposure sources of 10 metals (Vanadium, chromium, manganese, cobalt, nickel, copper, zinc, arsenic, cadmium, and lead) using principal component analysis (PCA) and then linked various principal component (PC) scores with environmental characteristics, including smoking-related indices, PM2.5, and distance to the nearest bus station. In addition, urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) and DNA hypomethylation markers (5-methyl-2'-deoxycytidine levels; %5-MedC) were investigated in combination with UC risks. We conducted this hospital-based case control study in 359 UC patients with histologically confirmed disease and 718 controls. All data were collected from face-to-face interviews and medical records. Approximately 6 mL blood was collected from participants for analysis of multiple heavy metal and DNA methylation in leukocyte DNA. Further, a 20 mL urine sample was collected to measure urinary cotinine and 8-OHdG levels. In addition, average values for PM2.5 for individual resident were calculated using the hybrid kriging/land-use regression model. In UC patients, significantly higher cobalt, nickel, copper, arsenic, and cadmium (μg/L) levels were observed in blood when compared with controls. Three PCs with eigenvalues > 1 accounted for 24.3, 15.8, and 10.7% of UC patients, and 26.9, 16.7, and 11.1% of controls, respectively. Environmental metal sources in major clusters were potentially associated with industrial activities and traffic emissions (PC1), smoking (PC2), and food consumption, including vitamin supplements (PC3). Multiple metal doses were linked with incremental urinary 8-OHdG and DNA hypomethylation biomarkers. For individuals with high PC1 and PC2 scores, both displayed an approximate 1.2-fold risk for UC with DNA hypomethylation.In conclusion, we provide a foundation for health education and risk communication strategies to limit metal exposure in environment, so that UC risks can be improved potentially.

The assessment of the soil-plant-animal transport of the risk elements at the locations affected by brown coal mining

The North Bohemian Brown Coal Basin (Czech Republic) is suggested as a source of significant pollution in the surrounding environment with various pollutants, including risk elements. A total of 53 sampling points were selected within the North Bohemian region. The selected sampling points represented either the basin areas (affected by the coal mining and related activities) or the mountain areas (an area unaffected by the coal mining but characterized by the geogenic sources of the risk elements). At each of the sampling points, soils and respective dominant indigenous plant samples were collected. A suite of ecological indices, namely, individual pollution index (Ii), Nemerow index (PN), bioaccumulation factor (BAF), translocation factor (TF), and hazard quotient (HQ), were applied to estimate the environmental risk of As, Be, Cd, and Zn levels in soils, potential soil-plant transfer, and soil-plant-animal transport of these stated elements. The results from Ii showed that the maximum values of As, Be, Cd, and Zn in the investigated soils exceeded the preventive values, where the Ii value was up to 58 for As in the mountain areas, indicating severe pollution. At the same time, mild pollution was recorded in the case of Cd. For Be in the researched soils, its Ii assessment result was a wide range, varying between a clean environment and severe pollution. Whereas As and Be uptake by plants was limited and these elements were retained in the plant's roots, relatively high mobility and soil to plant shoots transport ability of Cd were recorded and documented by the TF values. The HQs calculated for selected herbivorous mammals in the area showed that the potential health risk of As and Be was limited to only plant roots in the hotspots with extreme As and Be contents. In comparison, substantial health risk of Cd was observed in the aboveground biomass of plants. Therefore, the potential remediation of the coal mining areas should be focused on (i) identification of the As and Be hotspots and (ii) to reduce the mobility and plant availability of Cd in the whole investigated area.

Heavy metal assessment in agricultural soils and vegetables in the vicinity of industrial pollutants in the Pljevlja municipality (Montenegro): ecological and health risk approach

This paper aims to assess ecological and health risks associated with heavy metal (As, Hg, Cd, Pb, Cu, Zn, Cr) content in agricultural soils and vegetables (potato tuber, beetroot, onion bulb, carrot root) collected near the lead and zinc mine (MLZ), coal-fired power station (CFPS) and coal mine (CM) located in Pljevlja municipality (Montenegro). The ecological risk of soil was estimated using the ecological risk index (RI) and pollution load index (PLI). The health risk was evaluated through different soil exposure pathways (ingestion, inhalation, dermal contact) and vegetable consumption. The pollution indices RI and PLI indicated the highest contamination in MLZ study area followed by CM and CFPS areas. RI values revealed considerable contamination in MLZ and CM study areas, while CFPS area is moderately contaminated by heavy metals. According to PLI, soil in MLZ and CM areas is classified as polluted, while the soil in the vicinity of CFPS is classified as unpolluted. Non-carcinogenic and carcinogenic health risks through soil exposure were identified for both children and adults, in all investigated areas. Dermal contact was identified as the main contributor to carcinogenic risk. Dermal contact was also identified as the main exposure pathway for non-carcinogenic risk in MLZ area, while for CFPS and CM areas, ingestion was the main exposure route. As for vegetables, only Cu and Zn were detected in all examined vegetables. Non-cancerogenic health risk of edible vegetable consumption was found for children in all study areas, while there was no health risk for adults.

An integrated approach to quantify ecological and human health risks of soil heavy metal contamination around coal mining area

Soil heavy metals harm ecological biodiversity and human health, and quantifying the risks more accurately is still obscure. In this study, a network environ analysis was applied to quantify risks between ecological communities based on control allocation and human health risk models to calculate human health exposure risks from soil heavy metals around Greenside coal mining in South Africa. Ecological and human health risks were apportioned using PMF model. Results showed assessed heavy metals (mean) exceeded local background content with a cumulative of moderately polluted using pollution load index (PLI). Total initial risk (R_i), the risk to biological organisms from direct soil exposure, was 0.656 to vegetation and 1.093 to soil microorganisms. Risk enters the food web via vegetation and harms the whole system. Integrated risks (initial, direct, and indirect) to vegetation, herbivores, soil microorganisms, and carnivores were 0.656, 0.125, 1.750, and 0.081, respectively, revealing that soil microorganisms are the most risk receptors. Total Hazard Index (HI_T) was <1 for adults (0.574) whereas >1 for children (4.690), signifying severe non-cancer effects to children. Total cancer risk (TCR) to children and adults surpassed the unacceptable limit (1.00E-04). Comparatively, Cr is a high-risk metal accounted for 63.24% (adults) and 65.88% (children) of the HI_T and 92.98% (adults) and 91.31% (children) of the TCR. Four sources were apportioned. Contributions to R_i (soil microorganisms and vegetation) from F3 (industrial), F4 (atmospheric), F2 (coal mining), and F1 (natural) were 42.20%, 24.56%, 23.55%, and 9.68%, respectively. The non-cancer risk from F3 (37.67% to adults and 38.40% to children) was dominant, and TCR to children from the sources except F1 surpassed the unacceptable limit. An integrated approach of risk quantification is helpful in managing risks and reducing high-risk pollution sources to better protect the environment and human health.

Distribution of heavy metals in surface soil near a coal power production unit: potential risk to ecology and human health

Coal thermal power plants are the dominant factor in producing various hazardous elements in surrounding surface soil, resulting in a significant human health hazard. In the current study, the seasonal (pre- and post-monsoon) concentration of As, Cd, Co, Cr, Cu, Fe, Li, Mg, Mn, Ni, Pb, and Zn in surface soil around coal power production unit was analyzed using inductively coupled plasma-mass spectrometry (ICP-MS). The possible health risks throughout multiple exposure routes, i.e., ingestion, dermal, and inhalation were estimated for adult and children. Furthermore, geo-accumulation index (Igeo), enrichment factor (EF), pollution factor (CF), ecological risk index, and pollution load index (PLI) were applied to interpret the environmental pollution in the study area. The geospatial distribution pattern was computed to understand the trace and hazardous element distribution in the surface soil. As a result, the concentration of Fe (mg/kg) in pre-monsoon (15,620) and post-monsoon (27,180), Ni (mg/kg) in pre-monsoon (19.8), and post-monsoon (81.7) was found above the standard limits of soil prescribed by the WHO and FAO. Enrichment factor was observed between 0.95-6948 (pre-monsoon) and 0.53-116.09 (post-monsoon). The ecological risk index was found moderate to considerable for As and Cd metals during both seasons. In addition, the average PLI value was observed high for both seasons indicating the contamination of the study area with heavy metals. Moreover, Igeo values for Fe, Mg, and As were found relatively high. Conversely, health risks to the human population were found within the USEPA acceptable limits.

Legacy of anthropogenic lead in urban soils: Co-occurrence with metal(loids) and fallout radionuclides, isotopic fingerprinting, and in vitro bioaccessibility

Anthropogenic lead (Pb) in soils poses risks to human health, particularly to the neuropsychological development of exposed children. Delineating the sources and potential bioavailability of soil Pb, as well as its relationship with other contaminants is critical in mitigating potential human exposure. Here, we present an integrative geochemical analysis of total elemental concentrations, radionuclides of ¹³⁷Cs and ²¹⁰Pb, Pb isotopic compositions, and in vitro bioaccessibility of Pb in surface soils sampled from different locations near Durham, North Carolina. Elevated Pb (>400 mg/kg) was commonly observed in soils from urban areas (i.e., near residential house foundation and along urban streets), which co-occurred with other potentially toxic metal(loids) such as Zn, Cd, and Sb. In contrast, soils from city parks and suburban areas had systematically lower concentrations of metal(loids) that were comparable to geological background. The activities of ¹³⁷Cs and excess ²¹⁰Pb, coupled with their correlations with Pb and co-occurring metal(loids) were used to indicate the persistence and remobilization of historical atmospherically deposited contaminants. Coupled with total Pb concentrations, the soil Pb isotopic compositions further indicated that house foundation soils had significant input of legacy lead-based paint (mean = 1.1895 and 2.0618 for ²⁰⁶Pb/²⁰⁷Pb and ²⁰⁸Pb/²⁰⁶Pb, respectively), whereas urban streetside soils exhibited a clear mixed origin, dominantly of legacy leaded gasoline (1.2034 and 2.0416) and atmospheric deposition (1.2004-1.2055 and 2.0484-2.0525). The in vitro bioaccessibility of Pb in contaminated urban soils furthermore revealed that more than half of Pb in the contaminated soils was potentially bioavailable, whose Pb isotope ratios were identical to that of bulk soils, demonstrating the utility of using Pb isotopes for tracking human exposure to anthropogenic Pb in soils and house dust. Overall, this study demonstrated a holistic assessment for comprehensively understanding anthropogenic Pb in urban soils, including its co-occurrence with other toxic contaminants, dominant sources, and potential bioavailability upon human exposure.

Lipidomics of children and adolescents exposed to multiple industrial pollutants

BACKGROUND

There are limited studies on the lipidomics of children and adolescents exposed to multiple industrial pollutants.

OBJECTIVES

In this study, we aimed to investigate lipid profile perturbations in 99 children and adolescents (aged 9-15) who lived in a polluted area surrounding the largest petrochemical complex in Taiwan. Previous studies have reported increased risks of acute and chronic diseases including liver dysfunctions and chronic kidney disease (CKD) in residents living in this area.

METHODS

We measured urinary concentrations of 11 metals and metalloids and polycyclic aromatic hydrocarbons (PAHs) metabolite 1-hydroxypyrene (1-OHP) as exposure biomarkers, and urinary oxidative stress biomarkers and serum acylcarnitines as early health effect biomarkers. The association between individual exposure biomarkers and early health effect biomarkers were analyzed using linear regression, while association of combined exposure biomarkers with four oxidative stress biomarkers and acylcarnitines were analyzed using weighted quantile sum (WQS) regression. Lipid profiles were analyzed using an untargeted liquid chromatography mass spectrometry-based technique. "Meet-in-the-middle" approach was applied to identify potential lipid features that linked multiple industrial pollutants exposure with early health effects.

RESULTS

We identified 15 potential lipid features that linked elevated multiple industrial pollutants exposure with three increased oxidative stress biomarkers and eight deregulated serum acylcarnitines, including one lysophosphatidylcholines (LPCs), four phosphatidylcholines (PCs), and two sphingomyelins (SMs) that were up-regulated in high exposure group compared to low exposure group, and two LPCs, four PCs, and two phosphatidylinositols (PIs) down-regulated in high exposure group compared to low exposure group.

CONCLUSION

Our findings could provide information for understanding the health effects, including early indicators and biological mechanism identification, of children and adolescents exposed to multiple industrial pollutants during critical stages of development.

Evaluation and Integration of Geochemical Indicators for Detecting Trace Levels of Coal Fly Ash in Soils

Coal combustion residuals (CCRs), in particular, coal fly ash, are one of the major industrial solid wastes in the U.S., and due to their high concentrations of toxic elements, they could pose environmental and human health risks. Yet detecting coal fly ash in the environment is challenging given its small particle size. Here, we explore the utility and sensitivity of using geochemical indicators (trace elements, Ra nuclides, and Pb stable isotopes), combined with physical observation by optical point counting, for detecting the presence of trace levels of coal fly ash particles in surface soils near two coal-fired power plants in North Carolina and Tennessee. Through experimental work, mixing models, and field data, we show that trace elements can serve as a first-order detection tool for fly ash presence in surface soils; however, the accuracy and sensitivity of detection is limited for cases with low fly ash proportion (i.e., <10%) in the soil, which requires the integration of more robust Ra and Pb isotopic tracers. This study revealed the presence of fly ash particles in surface soils from both the recreational and residential areas, which suggests the fugitive emission of fly ash from the nearby coal-fired power plants.

Public health impact of coal-fired power plants: a critical systematic review of the epidemiological literature

Coal-based energy production is the most utilized method of electricity production worldwide and releases the highest concentration of gaseous, particulate, and metallic pollutants. Toxicological research has shown that coal combustion by-products are carcinogens, endocrine disruptors, and cardiorespiratory toxins. This article aims to systematically review the epidemiological literature on the impact emissions from coal-based power production has on morbidity and mortality worldwide. Two thousand one hundred and fifty-two articles were retrieved based on search criteria. Word search of abstract and article text filtered the results to 95 articles. Forty articles were included after screening. The literature indicates a significant adverse effect from particulate matter and polyaromatic hydrocarbon emissions on morbidity and mortality. There is a lack of consistency of exposure assessment and inadequate control of significant potential confounders such as social economic status. Future research should focus on improving exposure assessment models, specifically source-apportionment and geographic information system methods to model power plant-specific emissions.

Ecological restoration of coal fly ash-dumped area through bamboo plantation

The present study entails the phytoremediation potential of different bamboo species on 5-year-old FA-dumped site near Koradi thermal power plant of Nagpur, Maharashtra, India. The selected FA-dumped site was treated with farmyard manure, press mud, and bio fertilizer followed by plantation of six promising species of bamboo namely Bambusa balcooa Roxb., Dendrocalamus stocksii (Munro.) M. Kumar, Remesh and Unnikrishnan, Bambusa bambos (L.) Voss, Bambusa wamin E.G. Camus, Bambusa vulgaris var. striata (Lodd. ex Lindl.) Gamble, and Bambusa vulgaris var. vittata Riviere and Riviere. The experimental results indicated that the organic input in the FA-dumped site nourished the soil by improving its physico-chemical, and biological characteristics. The results revealed the contamination of the site with different trace elements in varied quantity including Cr (89.29 mg kg-1), Zn (84.77 mg kg-1), Ni (28.84 mg kg-1), Cu (22.91 mg kg-1), Li (19.65 mg kg-1), Pb (13.47 mg kg-1), and Cd (2.35 mg kg-1). A drastic reduction in concentration of heavy metals in FA was observed after 1 year of bamboo plantation as compared to the initial condition. The results showed that bamboo species are good excluders of Ba, Co, Cr, Li, Ni, Mn, and Zn, whereas they are good accumulators of Cd, Pb, and Cu. The values of biochemical parameters, such as pH, total chlorophyll, ascorbic acid (AA), and relative water content of all the bamboo leaves ranged from 5.11-5.70, 1.56-6.33 mg g-1, 0.16-0.19 mg g-1, and 60.23-76.68%, respectively. It is thereby concluded that the bamboo plantation with biofertilizers and organic amendments may indicate adaptive response to environmental pollution on FA-dumped site.

Effect of different industrial activities on soil heavy metal pollution, ecological risk, and health risk

Soil heavy metal (Cr, Cu, Zn, Pb, Cd, V, As) concentrations in different areas were analyzed to investigate the effects of different industrial activities on heavy metal pollution status, potential ecological risk, and human health risk in Panzhihua. Our results showed that Cu and V enrichment in soil was due to ore smelting. Soil Cr accumulation was related to coal ore mining. Soil Cd, Zn, As, and Pb enrichment was attributed to high-temperature coal combustion. Under the effect of industrial activities, soils were moderately contaminated with Cd, uncontaminated to moderately contaminated with As and Zn, and uncontaminated with Cr, Cu, V, and Pb. Soil heavy metal potential ecological risk was considerable, and non-carcinogenic risks and carcinogenic risks of soil heavy metals were acceptable for adults but unacceptable for children. Thermal power generation was the dominated industrial activity that influence the soil heavy metal concentrations and environmental risks in Panzhihua, which posed considerable potential ecological risks and unacceptable heavy metal non-carcinogenic risks and As carcinogenic risk to both adults and children. This study indicates that industrial activities have great effects on heavy metal pollution, ecological risks, and health risk, and more attention should be paid to the ecological risk and health risks brought by thermal power generation.

Geochemical assessment and spatial analysis of heavy metals pollution around coal-fired power station

Coal-fired power stations are significant sources of soil contamination with heavy metals and a source of hazard to human health. The soil samples (n = 25) selected in the area around Novocherkassk Power Station (Rostov Region, Russia) within a radius of up to 20 km revealed the enrichment with Pb, Cu and Zn. The heavy metals (HM) content in soil is reduced in the following sequence: Mn > Cr > Zn > Ni > Cu > Pb > Co. The correlation diagrams of the HM total content in soils revealed a significant association between the following HM pairs: Cu-Pb, Ni-Cu, Cd-Ni, Cd-Cu (r ≥ 0.7, p < 0.001). The concentration coefficient (Kc) and the total pollution coefficient (Zc) were used to estimate anthropogenic pollution. The use of generalized additive model (GAM) to detect the dependence of HM distribution on factors revealed the significance of the source distance. The influence of wind rhumb on HM distribution has a complex nonlinear nature. A GAM shows a good performance for all data sets: R² = 0.71, 81% deviance explained for Zn, R² = 0.85, 91% deviance explained for Cd, R² = 0.63, 70% deviance explained for Ni. Thus, GAM model reveals significant factors (Dist_km, rhumb) in forming pollution by heavy metals in studied impact zone and proved a valuable approach to assess the degree and sources of pollution in soils on a large scale.

Fly-Ash Pollution Modulates Growth, Biochemical Attributes, Antioxidant Activity and Gene Expression in Pithecellobium Dulce (Roxb) Benth

This study investigates the effect of fly ash (FA) on the Pithecellobium dulce (Roxb) Benth. trees growing at three different locations. FA stress caused significant changes in different leaf attributes like sugar, protein contents, photosynthetic pigments, nitrate content and nitrate reductase activity in foliar tissues of plants growing at a highly contaminated site, as compared to a low-pollution site. Lower rates of stomatal conductance (SC) were observed in P. dulce leaves under fly ash stress conditions that drastically reduced net photosynthetic rate (P_N); however, intercellular carbon dioxide concentration and stomatal index (SI) showed an increase under the same stress conditions. On the other hand, significant increase was also observed in the proline, sulphur and nitrogen contents. A significant increase in oxidative stress and, consequently, in antioxidant enzymes such as ascorbate peroxidase (APX), catalase (CAT), peroxidase (POD), and superoxidase dismutase (SOD) and Air pollution tolerance index were discovered at three different sites. The transcriptional expression of antioxidant and stress responsive genes was higher at HPS as compared to two other two sites of the study. Taken together the results demonstrated that the P. dulce is best suited as a fly ash stress tolerant plant species with the potential to provide an alternative for the reclamation of fly ash affected soils.

Mobility, distribution, and potential risk assessment of selected trace elements in soils of the Nile Delta, Egypt

Environmental pollution has received considerable attention over the last 50 years. Recently, there has been an increasing interest in pollution of the Nile Delta, Egypt, which is one of the longest settled deltaic systems in the world. Pollution in the delta is increasingly recognized as a serious health concern that requires proper management of ecosystems. Therefore, this project aimed to study the distribution and assess the risk associated with selected trace elements (TEs) in different soils (i.e., marine, fluvial, and lacustrine parent materials) in the northern Nile Delta. Mehlich-3 extraction was used to determine the availability of antimony, vanadium, strontium, and molybdenum in agro-ecosystems in this area and their spatial distributions were investigated. Five indices were used to assess ecological risk. Results showed that TEs were higher in the southern part of the study area because it is affected by multiple pollution sources. The available concentrations of TEs were Sr < V < Sb < Mo. The bioavailability of Sr was highest among the studied TEs. The studied indices suggested the study area was moderately polluted by Sr and Sb. Furthermore, the results showed that marine soils had higher TE levels then lacustrine and fluvial soils. The ecological risk assessment indicated that V and Mo were of natural origin, while Sr and Sb were anthropogenically linked. Therefore, the situation calls for planning to reduce pollution sources, especially in the protected north Nile Delta, so these productive soils do not threaten human and ecological health.

Metabolomics of Children and Adolescents Exposed to Industrial Carcinogenic Pollutants

Studies on metabolomes of carcinogenic pollutants among children and adolescents are limited. We aim to identify metabolic perturbations in 107 children and adolescents (aged 9-15) exposed to multiple carcinogens in a polluted area surrounding the largest petrochemical complex in Taiwan. We measured urinary concentrations of eight carcinogen exposure biomarkers (heavy metals and polycyclic aromatic hydrocarbons (PAHs) represented by 1-hydroxypyrene), and urinary oxidative stress biomarkers and serum acylcarnitines as biomarkers of early health effects. Serum metabolomics was analyzed using a liquid chromatography mass spectrometry-based method. Pathway analysis and "meet-in-the-middle" approach were applied to identify potential metabolites and biological mechanisms linking carcinogens exposure with early health effects. We found 10 potential metabolites possibly linking increased exposure to IARC group 1 carcinogens (As, Cd, Cr, Ni) and group 2 carcinogens (V, Hg, PAHs) with elevated oxidative stress and deregulated serum acylcarnitines, including inosine monophosphate and adenosine monophosphate (purine metabolism), malic acid and oxoglutaric acid (citrate cycle), carnitine (fatty acid metabolism), and pyroglutamic acid (glutathione metabolism). Purine metabolism was identified as the possible mechanism affected by children and adolescents' exposure to carcinogens. These findings contribute to understanding the health effects of childhood and adolescence exposure to multiple industrial carcinogens during critical periods of development.

Elemental Concentrations in Roadside Dust Along Two National Highways in Northern Vietnam and the Health-Risk Implication

There is a need to assess the risk of exposure to metals via roadside dust in Vietnam where many people live along the road/highways and are constantly exposed to roadside dust. In this study, we collected dust samples at 55 locations along two major Highways in north-east Vietnam, which passed through different land use areas. Samples were sieved into three different particle sizes and analyzed for concentrations of eight metals using a X-ray fluorescence instrument. The concentrations and environmental indices (EF, I _geo) of metals were used to evaluate the degree of pollution in the samples. Among different land uses, industrial areas could be highly polluted with heavy metals in roadside dust, followed by commerce and power plants. Additionally, the traffic density probably played an important role; higher concentrations were observed in samples from Highway No. 5 where traffic is several times higher than Highway No. 18. According to the risk assessment, Cr poses the highest noncarcinogenic risk even though the health hazard index values of assessed heavy metals in this study were within the acceptable range. Our assessment also found that the risk of exposure to heavy metals through roadside dust is much higher for children than for adults.

Linking sources to early effects by profiling urine metabolome of residents living near oil refineries and coal-fired power plants

BACKGROUND

This study aims at identifying metabolic changes linking external exposure to industrial air toxics with oxidative stress biomarkers.

METHODS

We classified 252 study subjects as 111 high vs. 141 low exposure subjects by the distance from their homes to the two main emission sources, oil refineries and coal-fired power plants. We estimated individual's external exposure to heavy metals and polycyclic aromatic hydrocarbons (PAHs) by dispersion and kriging models, respectively. We measured urinary levels of heavy metals and 1-hydroxypyrene (1-OHP) as biomarkers of internal exposure, and 8-OHdG, HNE-MA, 8-isoPGF_2α, and 8-NO₂Gua as biomarkers of early health effects. We used two-dimensional gas chromatography time-of-flight mass spectrometry to identify urine metabolomics. We applied "meet-in-the-middle" approach to identify potential metabolites as putative intermediate biomarkers linking multiple air toxics exposures to oxidative stress with plausible exposures-related pathways.

RESULTS

High exposure subjects showed elevated ambient concentrations of vanadium and PAHs, increased urine concentrations of 1-OHP, vanadium, nickel, copper, arsenic, strontium, cadmium, mercury, and thallium, and higher urine concentrations of all four urine oxidative stress biomarkers compared to low exposure subjects. We identified a profile of putative intermediate biomarkers that were associated with both exposures and oxidative stress biomarkers in participants. Urine metabolomics identified age-dependent biological pathways, including tryptophan metabolism and phenylalanine metabolism in children subjects (aged 9-11), and glycine, serine, and threonine metabolism in elderly subjects (aged>55), that could associate multiple exposures with oxidative stress.

CONCLUSION

By profiling urine biomarkers and metabolomics in children and elderly residents living near a petrochemical complex, we can link their internal exposure to oxidative stress biomarkers through biological pathways associated with common complex chronic diseases and allergic respiratory diseases. The internal exposure may possibly be traced to multiple air toxics emitted from specific sources of oil refineries and coal-fired power plants.

Human Health Risks Associated with Metals from Urban Soil and Road Dust in an Oilfield Area of Southeastern Algeria

Hassi Messaoud town is a recent city that is situated inside the oil field, which hosts an important petroleum extraction field and refinery. Large-scale and long-term oil refinery and corresponding industrial activities may contaminate the surrounding soil/dust and could lead to pollution levels that can affect human health. The soil and road dust samples were analysed for different trace elements: copper (Cu), manganese (Mn), nickel (Ni), lead (Pb), and zinc (Zn). Geo-accumulation index (I(geo)), pollution index (PI), and integrated pollution index (IPI) were calculated to evaluate the heavy metal contamination level of urban soil and road dust. The I(geo) values indicate unpolluted to moderate polluted of investigated metals in the soil samples. The assessment results of PI support the results of I(geo), and IPI indicates heavy metals in road dust polluted seriously. The noncarcinogenic health risk assessment shows that ingestion of soil/dust particles is the route for exposure to heavy metals, followed by dermal adsorption. The human exposure risk assessment based on different exposure pathways showed that the hazard index (HI) was <1.0 for all of the elements. The relative exposure risk (noncarcinogenic) was greater for toddlers. Although the overall risk was within the acceptable limit of 1.00, the HI of Pb from the soil (0.103) and road dust (0.132) was close to the threshold limits, which over the long-term may pose a health risk.