Potential Ecological Risk and Human Health Risk Assessment of Heavy Metal Pollution in Industrial Affected Soils by Coal Mining and Metallurgy in Ostrava, Czech Republic

Assessment of potential human health, radiological and ecological risks around mining areas in northeastern Brazil

Mining is responsible for the release of metallic pollutants and radioactive materials into the environment, which have the potential to disrupt ecosystems and pose significant risks to human health. Significant mining activity is concentrated in the municipality of Caetité (northeastern Brazil), where Latin America's only active uranium mine and significant iron ore deposits are located. Although previous studies have shown that the regional soil and water resources are highly contaminated by various toxic elements and that exposure to these elements is known to have adverse effects on human health, the health risks in this mining region have never been assessed. The aim of this unprecedented comprehensive investigation was to assess the health, radiological and ecological risks in this mining region, which is home to nearly 100,000 people. To achieve our goal, soil and water samples were collected in the vicinity of the mines and in the main settlements in the region. Fifteen metallic toxic elements were determined using Instrumental Neutron Activation Analysis and Inductively Coupled Plasma Optical Emission Spectrometry. The HERisk code, which follows the main methodological guidelines for risk assessment, was used to quantify human health, radiological and ecological indices. The average values of the total risk and cancer risk indices indicated that region falls into the moderate risk category (1.0 ≤ HItot < 4.0). However, 63% of the sites had high risk values, with Fe, Co and As being the metals contributing most to total and cancer risk, respectively. Near the mining areas, the potential ecological risk can be considered extreme (PERI ≥ 600). The values of the calculated radiological indices correspond to typical values ​​in natural uranium areas. However, in the communities near the mine, the dose values are slightly above the permissible limit (1 mSv y-1), so they must be continuously monitored, and risk mitigation measures must be taken.

Impact of solid waste dumping on soil quality and its potential risk on human health and environment

The soil, comprising minerals, organic matter, and living organisms, serves as a critical component of our environment. However, anthropogenic activities, such as uncontrolled sewage disposal and industrial waste, have led to pervasive soil pollution, impacting ecosystems and human health. This comprehensive study scrutinizes the intricate dynamics of soil pollution resulting from open waste dumping, specifically examining its impact on the health of local communities and the environment in Haridwar municipality. In this study, four solid waste dumping sites were meticulously surveyed, with soil samples analyzed for 19 parameters through statistical tools like one-way ANOVA, Kruskal-Wallis tests, soil pollution indices, and potential health risk assessment. The Geo-accumulation Index (Igeo) and contamination factor (CF) followed the heavy metals in the order of Zn > Mn > Fe > Cu in all selected sites. Additionally, a potential health risk assessment considered ingestion, inhalation, and dermal exposure pathways, revealing a high non-carcinogenic risk of metals (Mn > Fe > Zn > Cu) for both children and adults. In the ingestion pathway, the hazard quotient indicated a high risk of metals for both children and adults in the range of 1192.73 to 2066.94 for child and 191.98 to 312.16 for adults. Crucially, the HQ revealed potential health risks, emphasizing the urgency of addressing metal contamination. However, the findings indicate that dumping sites directly or indirectly affects the local people of Haridwar municipality. Therefore, this study provides a baseline framework for minimizing the impact of dumping sites on local population and the environment.

Distribution, mobilization, risk assessment and source identification of heavy metals and nutrients in surface sediments of three urban-rural rivers after long-term water pollution treatment

Sediments are critical pollution carriers in urban-rural rivers, which can threaten the water quality of the river and downstream lakes for a long time. However, it is still not clear whether conventional water pollution treatments could abate sediment pollution or not. In this study, heavy metals (HMs) and nutrient salts in the surface sediments and overlying water were investigated after decades' water pollution treatment in three urban-rural rivers. HM speciation was determined by the sequential extraction; diffusion fluxes were estimated using Fick's first law; HM ecological risk and nutrient pollution were evaluated; and pollution sources were identified by statistical analysis and GIS. The results showed that the HMs and nutrients were extremely serious in the urban regions. The accumulation level of Pb, Cu and Cd in the sediments of the three rivers were all much higher than the soil background value, and the labile fractions accounted for high proportions (57 % for Pb, 55 % for Cu and 43 % for Cd), which could be easily eluate from the sediments and caused hazards to the aquatic environment. The sediment diffusion fluxes of HMs and ammonia nitrogen were mostly positive, which indicated these sites currently released these pollutants from sediment to overlying water. Cd, Pb, Cu and Cr may mainly originate from industrial discharge and domestic sewage, while Cr was also greatly affected by crustal weathering; nutrient pollution may originate from agricultural activities and domestic sewage. Our study demonstrated that after decades' conventional water treatment in these rivers, the sediment pollution was still in a serious level with high ecological risk, and Cd was the dominant pollutant. At present, the external point source pollution has been effectively controlled, thus, the in-depth understanding of the sediment pollution characteristics after long-term water treatment could provide a scientific basis for the accurate elimination of river pollution.

Ecological risk assessment of heavy metal(loid)s in riverine sediments along the East China Sea: A large-scale integrated analysis

This study comprehensively assesses spatial distribution, pollution levels, and potential sources of heavy metal(loid)s in surface sediments across multiple river systems along the coastal area of the East China Sea. Copper in Qiantang River and Xiangshan Bay showed higher concentations and exceeded the threshold effect value, while the higher content of Lead was mainly found in the Saijiang River, Oujiang River, and Minjiang River. Heavy metal(loid)s in the alluvium of Qiantang River, Jiaojiang River, and Yangtze River showed low to moderate pollution levels, with Cd posing the highest ecological risk, followed by Hg. Meanwhile, Qiantang River, Jiaojiang River, Yangtze River, and Oujiang River exhibited considerable to moderate ecological risks and low toxic risk. PMF model analysis results reveal that concentrations of Cr, Ni, and As were closely related with natural geogenic input (36.56 %), while industrial and traffic activities (48.77 %) were primary source of Cu, Pb, Zn, and Hg, and main source of Cd was agricultural emissions (14.67 %).

Human health risk assessment due to consumption of dried fish in Chennai, Tamil Nadu, India: a baseline report

The current study sought to determine the levels of radioactivity and heavy metal contamination in 22 dried fish samples collected in Chennai, Tamil Nadu. The study found that there were substantial heavy metals concentrations for Pb, Mn, Cr, Co, and Cd. The concentration of heavy metal Pb being alarmingly high (32.85 to 42.09 mg/kg), followed by Cd (2.18 mg/kg to 3.51 mg/kg) than the permissible limit of WHO (2.17 mg/kg) for Pb and (0.05 mg/kg) for Cd. In terms of radioactivity, the gross alpha activity in the dried fish samples ranged 6.25 ± 0.12 to 48.21 ± 0.11 Bg/kg with an average of 20.35 Bg/kg and with a gross beta activity from 6.48 ± 0.02 to 479.47 ± 0.65 Bg/kg, for an average of 136.83 Bg/kg. The study found that the internal radiation dose that people receive upon consuming the fish species Sphyraena obtusata, Rachycentron canadum, Lepidocephalichthys thermalis, Synodontidae, Carangoides malabaricus, Sardina pilchardus, Scomberomorus commerson, Sillago sihama, Gerres subfasciatus, and Amblypharyngodon mola is above the ICRP-recommended limit of less than 1 mSv/year. Annual gonadal dose equivalent (AGDE) and total excessive lifetime cancer risk (ELCR) ranged 0.488 µSv year-1 and 0.004 µSv year-1 respectively, the values of AGDE being higher than the global average value. The findings of the study indicate that the analyzed dried fish samples are contaminated with Pb and Cd, which shall pose cancer risk to the consumers as a result.

Assessment of potentially toxic and mineral elements in paddy soils and their uptake by rice (Oryza sativa L.) with associated health hazards in district Malakand, Pakistan

Rice, a primary food source in many countries of the world accumulate potentially harmful elements which pose a significant health hazard to consumers. The current study aimed to evaluate potentially toxic and mineral elements in both paddy soils and rice grains associated with allied health risks in Malakand, Pakistan. Rice plants with intact root soil were randomly collected from paddy fields and analyzed for mineral and potentially toxic elements (PTEs) through inductively coupled plasma optical emission spectrometry (ICP‒OES). Through deterministic and probabilistic risk assessment models, the daily intake of PTEs with allied health risks from consumption of rice were estimated for children and adults. The results of soil pH (< 8.5) and electrical conductivity (EC > 400 μs/cm), indicated slightly saline nature. The mean phosphorus concentration of 291.50 (mg/kg) in soil samples exceeded FAO/WHO permissible limits. The normalized variation matrix of soil pH with respect to Ni (0.05), Ca (0.05), EC (0.08), and Mg (0.09), indicated significant influence of pH on PTEs mobility. In rice grains, the mean concentrations (mg/kg) of Mg (463.81), Al (70.40), As (1.23), Cr (12.53), Cu (36.07), Fe (144.32), Mn (13.89), and Ni (1.60) exceeded FAO/WHO safety limits. The transfer factor >1 for K, Cu, P and Zn indicated bioavailability and transfer of these elements from soil to rice grains. Monte Carlo simulations of hazard index >1 for Cr, Zn, As, and Cu with certainties of 89.93% and 90.17%, indicated significant noncarcinogenic risks for children and adults from rice consumption. The total carcinogenic risk (TCR) for adults and children exceeded the USEPA acceptable limits of 1×10-6 to 1×10-4, respectively. The sensitivity analysis showed that the ingestion rate was a key risk factor. Arsenic (As) primarily influenced total cancer risk (TCR) in children, while chromium (Cr) significantly impacted adults. Deterministic cancer risk values slightly exceeded probabilistic values due to inherent uncertainties in deterministic analysis. Rice consumption poses health risks, mainly from exposure to Cr, Ni and As in the investigated area.

Assessment of the ecological risk and mobility of arsenic and heavy metals in soils and mine tailings from the Carmina mine site (Asturias, NW Spain)

An evaluation of the pollution, distribution, and mobility of arsenic and heavy metals in spoil heaps and soils surrounding the abandoned Carmina lead-zinc mine (Asturias, northern Spain) was carried out. Fractionation of arsenic was performed by an arsenic-specific sequential extraction method; while, heavy metal fractionations was carried out using the protocol of the Bureau Community of Reference (BCR) (now renamed Standards, Measurements and Testing Programme). Arsenic appeared predominantly associated with amorphous iron oxyhydroxides. Among the heavy metals, lead and zinc showed high availability since significant amounts were extracted in the nonresidual fractions; whereas, chromium, copper and nickel showed very low availability, indicating their lithogenic origins. The results showed that the extractability of heavy metals in soils is influenced mainly by the presence of iron and manganese oxides as well as by pH and Eh. Multiple pollution indices, including the enrichment factor (EF), geoaccumulation index (Igeo), ecological risk index (Er) and potential ecological risk index (PERI), were used to assess the degree of soil pollution in the mine area. All results showed that lead was the key factor causing the pollution and ecological risk in the studied area, and copper, zinc and arsenic also had significant contributions. Notably, the sites at higher risk coincided with those with high availability of arsenic and heavy metals. This study provides an integrative approach that serves as a powerful tool to evaluate the metal pollution status and potential threats to the local environment of abandoned mining areas, and the results are useful for making management decisions in these areas.

Distribution, Source, and Ecological Risk of Heavy Metals in Sewage Irrigation of Taiyuan, Shanxi Province, China

The pollution of agricultural soil by heavy metals is a significant environmental issue that has a serious impact on human health and food security. This study focused on investigating the presence of heavy metal pollution in sewage-irrigated soils in Taiyuan city. A total of 110 soil samples were analyzed for the presence of As, Hg, Cd, Pb, Cr, Cu and Zn. The results showed that the concentrations of these metals ranged from 0.06 to 26.74 mg/kg for As, 0.00 to 0.84 mg/kg for Hg, 0.03 to 0.69 mg/kg for Cd, 44.32 to 100.09 mg/kg for Pb, 9.85 to 42.19 mg/kg for Cr, 13.38 to 53.72 mg/kg for Cu, and 42.77 to 145.47 mg/kg for Zn. The average concentrations of these metals were found to be below the risk values specified in the "Soil environmental quality (GB15618-2018)", except for As and Cd in three sampling points in Xiaodian District. The heavy metal pollution in these areas can be attributed to various sources, such as industrial activities, the use of fertilizers and pesticides, and the irrigation process. According to the geo-accumulation index, the agricultural soil in the Taiyuan irrigation area was found to be uncontaminated by Zn, Cr, Cu, and As, and lightly contaminated by Cd, Hg, and Pb. The Nemerow Pollution Index indicated that the soil at all sampling points exhibited a slight level of pollution. Moreover, the ecological risk assessment indicated that all heavy metals posed a slight level of pollution. The findings of this study provide a scientific basis for the development of effective policies and measures for soil environmental protection and pollution control.

Advanced biotechnology strategies for detoxification of persistent organic pollutants and toxic elements in soil

This paper aims to comprehensively examine and present the current state of persistent organic pollutants (POPs) and toxic elements (TEs) in soil. Additionally, it seeks to assess the viability of employing advanced biotechnology, specifically phytoremediation with potent microbial formulations, as a means of detoxifying POPs and TEs. In the context of the "global treaty," which is known as the Stockholm Convention, we analyzed the 3D chemical structures of POPs and its prospects for living organisms which have not been reviewed up to date. The obstacles associated with the phytoremediation strategy in biotechnology, including issues like slow plant growth and limited efficiency in contaminant uptake, have also been discussed and demonstrated. While biotechnology is recognized as a promising method for detoxifying persistent organic pollutants (POPs) and facilitating the restoration of contaminated and degraded lands, its full potential in the field is constrained by various factors. Recent advances in biotechnology, such as microbial enzymes, designer plants, composting, and nanobiotechnology techniques, have opened up new avenues for mitigating persistent organic pollutants (POPs) and toxic elements (TEs). The insights gained from this review can contribute to the development of innovative, practical, and economically viable approaches for remediating and restoring soils contaminated with persistent organic pollutants (POPs) and toxic elements (TEs). The ultimate aim is to reduce the risks to both human and environmental health.

Health risk assessment of heavy metal pollution and its sources in agricultural soils near Hongfeng Lake in the mining area of Guizhou Province, China

Background

Accelerated modern industrial processes, extensive use of pesticides and fertilizers and remaining issues of wastewater irrigation have led to an increasingly severe composite pollution of heavy metals in arable land. Soil contamination can cause significant damage to ecological environments and human health. Mineral resource mining can result in varying degrees of heavy metal pollution in surrounding water systems and soil. As a plateau lake, Hongfeng Lake has a fragile watershed ecosystem. Coupled with the rapid development of the current socio-economy and the ongoing activities of mining, urbanization and agricultural development, the water and soil environment of the lake and arable land are facing serious heavy metal pollution. Therefore, the situation warrants attention.

Methods

This study focused on characterizing soil types and conducted sampling and laboratory testing on the farmland soil in Hongfeng Lake. The integrated Nemero comprehensive pollution assessment and potential ecological pollution assessment methods were used to evaluate the heavy metal pollution status. The APCS-MLR model was employed to explore the sources of heavy metal pollution. In addition, the human health risk model was used to analyze the association between heavy metal content in cultivated land and human health risks.

Results

The single-factor pollution of each element was ranked in descending order: Hg > As > Pb > Cr > Cd, with Hg being the main pollutant factor. The entire area was subjected to mild pollution according to the pollution index. Pollution source analysis indicated two main pollution sources. Hg, As, Pb and Cr pollution mainly resulted from Source 1 (industrial and natural activities), accounting for 71.99%, 51.57%, 67.39% and 68.36%, respectively. Cd pollution was mainly attributed to Source 2 (agricultural pollution source), contributing 84.12%. The health risk assessment model shows that heavy metals posed acceptable carcinogenic risks to humans rather than non-carcinogenic risks. As was the main non-carcinogenic risk factor, while Cr was the main carcinogenic risk factor, with higher risks in children than adults.

Conclusion

Our study identified the heavy metal pollution in farmland soil in Hongfeng Lake, evaluated and analyzed the pollution sources and identified the heavy metal elements in cultivated lands that have the greatest impact on human health risks. The aim of this study is to provide a scientific basis for soil heavy metal pollution control.

An overview of the impacts of coal mining and processing on soil: assessment, monitoring, and challenges in the Czech Republic

Coal mining activities are causing an extensive range of environmental issues at both operating and abandoned mine sites. It is one of the most environmentally destructive practices, with the capability to eliminate fauna and flora, impact the groundwater system, and pollute the soil, air, and water. The Czech Republic relies almost exclusively on coal as its primary domestic source of energy. The combined reserves of hard and brown coals in this country are 705 million tons. About 50 million tons of coal is produced annually, making it the 14th biggest producer in the world. Soil degradation is an inevitable outcome of the coal production from surface coal mining procedures in the Czech Republic. Significant changes have taken place in soil productivity, hydraulic characteristics, horizon, and texture as a result of soil pollution, bioturbation, compaction, and weathering. The current review has evaluated the impact of reclamation and coal mining on soil characteristics, including biological, chemical, and physical properties. Additionally, the study has outlined the process of soil formation in reclamation areas in the Czech Republic. In nutshell, research gaps and future directions in understanding coal mining areas and their influences on soils in the Czech Republic are identified.

Trace element contamination in soils surrounding the open-cast coal mines of eastern Raniganj basin, India

Trace element pollution of soils surrounding coal-mining areas affects the health of local communities. The increasing coal-mining and associated activities in the Raniganj basin (east India) have led to increased soil concentration of certain trace elements. To quantify the elevated trace element (TE) concentrations in the soil surrounding coal-mining areas, 83 surface soil, coal, and shale samples were collected from open-cast mining areas of the eastern Raniganj basin. The soils present are sandy silt, silty sand, and silty in nature, but almost no clay. They are acidic (pH = 4.3) to slightly alkaline (pH = 7.9) with a mean electrical conductivity (EC) of 340.45 µS/cm and a mean total organic carbon (TOC) of 1.80%. The northern and western parts of the study area were found to be highly polluted by certain metallic trace elements. The relevant environmental indices, geoaccumulation index (Igeo), contamination factors (CF), enrichment factors (EF), and pollution load index (PLI) were calculated and assessed. Analysis revealed that Cr was highly enriched in these soil samples, followed by Pb, Co, Cu, Cd, Fe, Ni, Mn, Zn, As, and Al. Geostatistical analyses (correlation coefficients and principal component analysis) indicated that the occurrence of some trace elements (Al, Cd, Co, Cu, Fe, Mn, Ni, and Zn) is most likely linked to the various coal-mining operations in the study area. However, the anomalous Cr and Pb distributions are likely influenced by other anthropogenic, mainly industrial, inputs besides coal mining. These results justify the adoption of rigorous soil monitoring programs in the vicinity of coal-mining areas, to identify pollution hotspots and to develop strategies to reduce or mitigate such environmentally damaging pollution.

Associations between migraine and possible risk factors in the Czech Republic

Introduction

Migraine is a widespread neurological disorder, growing increasingly common. However, the pathogenesis of the disease is often unclear and the evidence for the role of various risk factors is limited. This study aimed to identify risk factors associated with migraine and to contribute towards a better understanding of this disease.

Methods

Data from 3,247 questionnaires were analyzed for associations between migraine and sex, age, BMI, degree of education, and air pollution, along with other factors such as contact with friends, physical condition, health, anxiety, and depression. A cross-sectional study was conducted with an approximately equal distribution of the sample by age, gender and two analysed regions. Data were presented using basic descriptive statistics using the chi-square test. The model output was presented using a crude odds ratio (OR) and a fully adjusted OR. Three hundred and eight-six individuals (12%) suffered from migraine.

Results

In an adjusted model, the presented study found associations between the prevalence of migraine and sex, age, and level of education. Individuals with migraine statistically significantly more often suffered from depression, anxiety and other selected factors. However, the assumed significant association between the occurrence of migraine and pollution in the region has not been found.

Soil contamination by trace metals and assessment of the risks associated: the dumping site of Safi city (Northwest Morocco)

The main objective of this work was to determine the soil contamination with trace metals within and around the dumpsite of Safi city (Morocco) and to evaluate the potential environmental risk associated. The results showed that the average soil concentrations of trace metals had the following order: Fe > Zn > Cu > Cr > Cd and exceeded the world and the upper continental background concentrations except for Fe. In addition, the concentrations of Zn, Cu, and Cd remained beyond the limit standards given by the WHO/FAO. Geoaccumulation index, enrichment factor, and pollution load index (PLI) indicated that the dumpsite soil is highly contaminated and deteriorated, presenting evidence of high ecological risk proved by the values of the potential ecological risk index (PERI). Correlation analyses revealed a strong relationship between the organic matter & [Fe, Zn, Cr, Cd], calcium carbonates & [Zn, Cr], and Cr & Cu inside the dumpsite soil. Principal component analysis confirmed the temporal and spatial classification of Zone A as the oldest and Zone C as the youngest and indicated that the regrouped trace metals could have the same behavior and or the same origin. The interpolation of trace metals concentrations and PERI revealed a plausible extension outside the landfill, confirmed by PLI values.

A case study of environmental pollution by pathogenic bacteria and metal(oid)s at Soran Landfill Site, Erbil, Iraqi Kurdistan Region

Environmental pollution is a serious issue all around the world, especially when it is caused by metal(oid)s and pathogenic microorganisms. This study reports here for the first time on the contamination of soil and water with metal(oid)s and pathogenic bacteria directly resulting from the Soran Landfill Site. Soran landfill is a level 2 solid waste disposal site that lacks leachate collection infrastructure. The site is potentially an environmental and public hazard caused by metal(oid)s content and significantly dangerous pathogenic microorganisms through leachate release into the soil and nearby river. This study reports on the levels of the metal(oid)s content of As, Cd, Co, Cr, Cu, Mn, Mo, Pb, Zn, and Ni obtained by inductively coupled plasma mass spectrometer in soil, leachate stream mud, and leachate samples. Five pollution indices are used to assess potential environmental risks. According to the indices, Cd and Pb contamination is significant, whereas As, Cu, Mn, Mo, and Zn pollution is moderate. A total of 32 isolates of bacteria were defined from soil, leachate stream mud, and liquid leachate samples: 18, 9, and 5, respectively. Moreover, 16 s rRNA analysis suggested that the isolates belong to three enteric bacterial phyla of Proteobacteria, Actinobacteria, and Firmicutes. The closest GenBank matches of 16S rDNA sequences indicated the presence of the genera: Pseudomonas, Bacillus, Lysinibacillus, Exiguobacterium, Trichococcus, Providencia, Enterococcus, Macrococcus, Serratia, Salinicoccus, Proteus, Rhodococcus, Brevibacterium, Shigella, Micrococcus, Morganella, Corynebacterium, Escherichia, and Acinetobacter. The identity percentage was mostly between 95%-100%. The results of this study show the levels of microbiological and geochemical contamination of soils, surface and potentially ground water with harmful microorganisms and toxic metal(oid)s originating specifically from Soran landfill leachate which subsequently incorporated into the surrounding environment, creating thus a considerable health and environmental risk.

Seasonal variation and risks of potentially toxic elements in agricultural lowlands of central Cameroon

Intensive urban agriculture is expanding in Cameroon, which increases the risks of environmental pollution, particularly in the lowlands. This study assessed the seasonal characteristics of some potentially toxic elements and their ecological risks during the dry and wet seasons in urban agricultural soils in four lowlands in Yaoundé. The area and seasonal variation of some potentially toxic elements (Cu, Pb, Zn, Cd, Cr, and Ni) were evaluated using mixed-effects modeling. The pollution status of these elements in the soil was evaluated and interpreted using parameters such as the single pollution (SPI) and Nemerow composite pollution (NCPI) indices. In addition, the effect of these metals in the environment was assessed using the potential ecological risk index (PERI). The distribution of all the studied elements showed an area effect, while a seasonal effect was only noticeable for Cu. The concentration of Cu, Pb, and Zn was higher than the recommended threshold values in one of the areas sampled, while Cr exceeded these threshold values in all areas during both seasons. Cr exhibited the highest SPI among all studied elements during the dry and wet seasons in all areas. Except for the NCPI in one area, where grade V (strong) soil pollution was recorded during the wet season, the soil from all the study areas exhibited a slight pollution level (grade III) with a mean NCPI between 1 and 2. The PERI value of all areas was below the reference values during both seasons, suggesting an overall low potential contamination risk of the soil biota. The results indicate that preventive action to limit the heavy metal contamination in the lowlands of Yaoundé needs to be taken, for instance, through the promotion of more sustainable use of agrochemicals like pesticides and mineral fertilizers.

Spraying Zinc Sulfate to Reveal the Mechanism through the Glutathione Metabolic Pathway Regulates the Cadmium Tolerance of Seashore Paspalum (Paspalum vaginatum Swartz)

Cadmium (Cd) is considered to be one of the most toxic metals, causing serious harm to plants' growth and humans' health. Therefore, it is necessary to study simple, practical, and environmentally friendly methods to reduce its toxicity. Until now, people have applied zinc sulfate to improve the Cd tolerance of plants. However, related studies have mainly focused on physiological and biochemical aspects, with a lack of in-depth molecular mechanism research. In this study, we sprayed high (40 mM) and low (2.5 mM) concentrations of zinc sulfate on seashore paspalum (Paspalum vaginatum Swartz) plants under 0.5 mM Cd stress. Transcriptome sequencing and physiological indicators were used to reveal the mechanism of Cd tolerance. Compared with the control treatment, we found that zinc sulfate decreased the content of Cd2+ by 57.03-73.39%, and that the transfer coefficient of Cd decreased by 58.91-75.25% in different parts of plants. In addition, our results indicate that the antioxidant capacity of plants was improved, with marked increases in the glutathione content and the activity levels of glutathione reductase (GR), glutathione S-transferase (GST), and other enzymes. Transcriptome sequencing showed that the differentially expressed genes in both the 0.5 Zn and 40 Zn treatments were mainly genes encoding GST. This study suggests that genes encoding GST in the glutathione pathway may play an important role in regulating the Cd tolerance of seashore paspalum. Furthermore, the present study provides a theoretical reference for the regulation mechanism caused by zinc sulfate spraying to improve plants' Cd tolerance.

Ecological and health risks from heavy metal sources surrounding an abandoned mercury mine in the island paradise of Palawan, Philippines

A recent survey that determined heavy metal concentrations in an abandoned Hg mine in Palawan, Philippines, found the occurrence of Hg with As, Ba, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Sb, Tl, V, and Zn. While the Hg originated from the mine waste calcines, the critical knowledge about the origin of the other heavy metals remains unknown. This study assessed the ecological and health risks from heavy metal pollution surrounding the abandoned Hg mine. Principal component analysis (PCA) showed that the abandoned mine and natural sources (i.e., local geology) are the two main contributors of heavy metal pollution. Historically, the mine waste calcines (retorted ore) were used as construction material for the wharf and as land filler for the adjacent communities. There is highly strong ecological risk associated with the heavy metals: Ni, Hg, Cr, and Mn contribute 44.3%, 29.5%, 10.7%, and 8.9% to the potential ecological risk index (RI), respectively. Hazard index (HI) exceeded 1 for both adults and children in all the sampling locations, implying non-carcinogenic adverse effects. The total cancer risk over a lifetime (LCR) also exceeded the threshold limit of 10^-4 for both adults and children, contributed mainly by Cr (91.8%) and As (8.1%). By combining the results of the PCA and risk assessments, a clear link between heavy metal source apportionment to ecological and health risks was established. It was estimated that the abandoned mine contributed to most of the ecological and health risks for people living near the wharf that was built using the calcine, as well as the nearby Honda Bay. The findings of this study are expected to help policy makers develop regulations that will safeguard the ecosystem and the general public from the damaging impacts of heavy metals from the abandoned mine.

Spatial distribution, source apportionment, and ecological risk assessment of elements (PTEs, REEs, and ENs) in the surface soil of shiraz city (Iran) under different land-use types

In this study, 100 samples were collected from the topsoil of different land-use types (urban, industrial and agricultural) in Shiraz. The content of 26 elements was analyzed. CF, EF, Igeo, NPI, and PLI indices were used to evaluate soil pollution. Ecological risk assessment of metals was calculated by using Er and RI indexes. PCA analysis and the PMF model were used to determine the source of metals in soil. Also, the spatial distribution of metals and risk index were plotted using inverse distance weighting (IDW) with ArcGIS software (10.3). The metal concentrations in the soil ranged from 0.2067 ± 0.0946 (Ag) to 85,673.50 ± 4689.27 (Ca) mg kg^-1. The results show that all elements' Concentration in soils was lower than the DOE level. The mean concentration of All rare earth elements (REEs) was lower than WSA and ECM values. Hotspot points pollution of some metals such as Pb, Cd, and Ni are located in high-traffic parts of the urban area. Otherwise, hot spot points of As pollution are located in industrial sample points. Results of indexes show that Sb in urban and agricultural soils have highe mean values of CF (6.75 and 6.85) and Iegeo (2.17 and 2.13), respectively. In industrial soils, S has highe mean values of CF (14.95), EF (100.26), and Igeo (2.95). The PLI index shows that REEs (PLI <1) have no pollution, but PTEs and ENs have pollution (PLI >1). The mean Er, value shows that Sb (127.33) and Cd (104) have significant risk among metals. PCA and PMF models show that The main sources of elements in shiraz soil are vehicularly emitted, fertilizer use, sewage irrigation, atmospheric deposition, and parent material. Generally, results show that Most of the study area has considerable risk, especially concerning PTEs. So, it is recommended to pay more attention to the issue of traffic in the urban environment in to improve the state of the urban area.

Health and environmental impact assessment of landfill mining activities: A case study in Norfolk, UK

The release of fine particles during mechanical landfill mining (LFM) operations is a potential environmental pollution and human health risk. Previous studies demonstrate that a significant proportion (40–80% wt) of the content of fine soil-like materials within the size range <10 mm to <4 mm recovered from such operations originate from municipal solid waste (MSW) landfills. This study evaluates the potential health risks caused by emissions from LFM activities. MSW samples recovered from the drilling of four different wells of a closed UK landfill were analysed for physical, chemical, and biological properties to determine the extent of potential contaminant emissions during LFM activities. The results show that fine particles (approximately ≤1.5 mm) accounted for more than 50% of the total mass of excavated waste and contained predominantly soil-like materials. The concentrations of Zn, Cu, Pb, Cd, As, and Cr exceed the permissible limits set by the current UK Soil Guideline Values. The highest geoaccumulation index and contamination factor values for Cu were 2.51 and 12.51, respectively, indicating a moderate to very high degree of contamination. Unsurprisingly, the pollution load index was >1, indicating the extent of pollution within the study area. The hazard quotient values indicated high exposure-related risks for Pb (16.95), Zn (3.56), Cd (1.47), and As (1.46) for allotment land use and As (1.96) for residential land use. The cancer-related risk values were higher than the acceptable range of 1.0 × 10⁻⁶ to 1.0 × 10⁻⁴. The cancer risk factor indicated that Cr and As were the major human health risk hazards.

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Potentially toxic elements and organics associated with waste fine fractions.

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Novel method for assessing potential human health risk of heavy metals achieved.

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Landfill poses major risk to human health and environment if LFM occurs.

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Pb highest contributor to the non-carcinogenic risk.

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Cr most prominent metal with respect to carcinogenic effect.

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.

Direct determination of Cu, Cr, and Ni in river sediments using double pulse laser-induced breakdown spectroscopy: Ecological risk and pollution level assessment

Double pulse laser-induced breakdown spectroscopy (DP LIBS) has attracted much attention for analyzing trace elements due to its higher sensitivity when compared to single pulse laser-induced breakdown spectroscopy (SP LIBS). However, the development of quantitative methods in LIBS for the analysis of complex samples, such as sediments, is a great challenge due to the matrix effects that are very accentuated in this technique. In this study, different spectral treatments and calibration strategies were investigated to obtain calibration models that allow determinations with satisfactory accuracy and precision of Cr, Cu, and Ni in river sediments from different hydrographic basins. The best model developed for Cr was using MMC without spectral normalization and for Cu and Ni it was using MMC with spectral normalization, and using inverse regression, an increase in the accuracy of the determinations of all analytes was obtained. These models showed limit of quantification (LOQ) of 7.87 mg kg^-1, 1.62 mg kg^-1, and 2.21 mg kg^-1 and root mean square error of prediction (RMSEP) of 7.54 mg kg^-1, 14.53 mg kg^-1, and 8.29 mg kg^-1 for Cr, Cu, and Ni, respectively. Therefore, the models have adequate sensitivity and precision for the quantification of the potentially toxic elements (PTEs) evaluated, since, according to Brazilian legislation, the lower concentration of threshold effect level (TEL) for Cr, Cu, and Ni is <37.3 mg kg^-1, <35.7 mg kg^-1, and <18 mg kg^-1, respectively. The concentrations of Cr, Cu, and Ni determined by DP LIBS allowed to obtain a partial ecological risk assessment of the studied sediments. Also, the chemometric tool Kohonen self-organizing map (KSOM) were used for data interpretation.

Spatial Distribution, Contamination Levels, and Health Risk Assessment of Potentially Toxic Elements in Household Dust in Cairo City, Egypt

Urban areas’ pollution, which is owing to rapid urbanization and industrialization, is one of the most critical issues in densely populated cities such as Cairo. The concentrations and the spatial distribution of fourteen potentially toxic elements (PTEs) in household dust were investigated in Cairo City, Egypt. PTE exposure and human health risk were assessed using the USEPA’s exposure model and guidelines. The levels of As, Cd, Cr, Cu, Hg, Mo, Ni, Pb, and Zn surpassed the background values. Contamination factor index revealed that contamination levels are in the sequence Cd > Hg > Zn > Pb > Cu > As > Mo > Ni > Cr > Co > V > Mn > Fe > Al. The degree of contamination ranges from considerably to very high pollution. Elevated PTE concentrations in Cairo’s household dust may be due to heavy traffic emissions and industrial activities. The calculated noncarcinogenic risk for adults falls within the safe limit, while those for children exceed that limit in some sites. Cairo residents are at cancer risk owing to prolonged exposure to the indoor dust in their homes. A quick and targeted plan must be implemented to mitigate these risks.

Impact of Industrially Affected Soil on Humans: A Soil-Human and Soil-Plant-Human Exposure Assessment

Heavy metal (HM) contaminated soil can affect human health via ingestion of foodstuffs, inhalation of soil dust, and skin contact of soil. This study estimates the level of some heavy metals in soils of industrial areas, and their exposures to human body via dietary intake of vegetables and other pathways. Mean concentrations of Cr, Fe, Cu, Zn, As and Pb in the studied soil were found to be 61.27, 27,274, 42.36, 9.77, 28.08 and 13.69 mg/kg, respectively, while in vegetables the respective values were 0.53, 119.59, 9.76, 7.14, 1.34 and 2.69 mg/kg. Multivariate statistical analysis revealed that Fe, Cu, Zn, and Pb originated from lithogenic sources, while Cr and As are derived from anthropogenic sources. A moderate enrichment was noted by Cr, As, and Pb in the entire sampling site, indicating a progressive depletion of soil quality. The bioaccumulation factor (BCF) value for all the vegetables was recorded as BCF < 1; however, the metal pollution index (MPI) stipulates moderately high value of heavy metal accumulation in the vegetable samples. Hazard Index (HI) of >0.1 was estimated for adults but >1 for children by direct soil exposure, whereas HI < 1 for both children and adults via dietary intake of vegetables. Estimated Total carcinogenic risk (TCR) value due to soil exposure showed safe for adults but unsafe for children, while both the population groups were found to be safe via food consumption. Children are found more vulnerable receptors than adults, and health risks (carcinogenic and non-carcinogenic) via direct soil exposure proved unsafe. Overall, this study can be used as a reference for similar types of studies to evaluate heavy metal contaminated soil impact on the population of Bangladesh and other countries as well.

Ecological Characterization and Bio-Mitigation Potential of Heavy Metal Contamination in Metallurgically Affected Soil

Heavy metals (HMs) remain persistent in soil for a long time and thus present a long-term threat of environmental pollution. In this study, the concentrations of some HMs (As, Cu, Zn, Pb, and Mo) in soil, potentially affected by the ex-operation of a metallurgical plant—specifically, a copper smelter in Alaverdi Town, northeastern Armenia—were measured, based on which, the HM contamination and its ecological, biological, and health effects were assessed. Concentrations of HMs (Cu, Zn, and Pb) were also measured in different plant (leaves) and invertebrate species that occur in the soil over the metallurgical factory site in order to assess the potential for the bioremoval of HMs from the soil. The results showed that the ex-operation of the metallurgical facility created such contamination in the soil that it caused a noticeable loss of invertebrate biomass in the soil and posed ecological, non-carcinogenic (for children), and carcinogenic health hazards. The investigated plant and invertebrate species were characterized by different capacities for the accumulation of HMs from the soil, based on which the plant species Fraxinus excelsior, Acer platanoides, Robinia pseudoacacia, and Aesculus hippocastanum and the invertebrate species Deroceras caucasicum, Limax flavus, and Eisenia rosea are recommended to be used for the selective removal of HMs (Cu, Zn, and Pb) from the soil.

Characteristics and Risk of Forest Soil Heavy Metal Pollution in Western Guangdong Province, China

West Guangdong is an important ecological barrier in Guangdong province, so understanding the spatial patterns and sources of heavy metal pollution of forest soil in this region is of great significance for ecological protection. In this study, the concentrations of heavy metals (Cd, Pb, Cu, Zn, and Ni) in forest soil were determined. Geostatistics, single-factor pollution index (PI), potential ecological risk index (RI), principal component analysis (PCA), and Pearson’s correlation analysis were used to evaluate and analyze the characteristics of heavy metal pollution of forest soil. The results showed that the average concentration did not exceed the critical value. Cd, Pb, and Cu were enriched in southwest Xinxing County, while Zn and Ni were enriched in most areas of the Yunan and Yuncheng districts. Two groups of heavy metals from different sources were identified by PCA and a correlation analysis. Cd, Pb, and Cu in their respective enrichment areas were mainly from marble and cement production, whereas Zn and Ni were primarily from transportation and chemical fertilizer. Most of the study area was safe or slightly polluted while the heavy metal-enriched areas were moderately to severely polluted. The potential ecological risk was at a lower level in the study area but moderate in southwest Xinxing County. In summary, human factors impact the spatial patterns and ecological risks of heavy metals in forest soil. This study provides a scientific basis for forest soil pollution control and ecological protection.

A risk assessment by metal contamination in a river used for public water supply

Aquatic ecosystems provide habitats for many organisms. Historically, riverbanks have always been inhabited and exploited for subsistence and navigation. The present study evaluates the contamination and ecological risks caused by potentially toxic elements in surface sediments of the Paraguaçu River, Bahia, Brazil. Seven sediments samples were collected, and eight heavy metals were determined employing inductively coupled plasma spectrometry mass (ICP-MS). The concentrations range as (mg kg^-1) found were 6.78-18.68 for lead, 14.21-42.16 for zinc, 27.61-48.63 for nickel, 2.03-6.50 for chromium, 6.06-12.90 for vanadium, 5.99-13.33 for cupper, 1.25-3.19 for cobalt, and 79.52-286.08 for manganese. Nickel showed significant enrichment (EF: 5.75; 7.62, and 14.11), followed by zinc, which showed moderate enrichment (EF: 2.16; 2.19, and 4.52). These enrichment levels are possible of anthropogenic origin. When the pollution index (PI) was evaluated, the elements V, Ni, Zn, Mn, Co, and Cu were strongly polluted (PI ≥3). In general, the pollution index (PI), geoaccumulation index (I_geo), enrichment factor (EF), and potential ecological risk indices (E_r and PERI) show that contaminated sediments have adverse effects on aquatic environments, especially for o Mn, Ni, Pb, V, and Zn.

Heavy metals and health risk assessment in vegetables grown in the vicinity of a former non-metallic facility located in Romania

Soil contamination represents a serious and significant issue, especially when it comes to soil used in agricultural practices. This research was carried out in order to investigate the accumulation level of potentially toxic trace elements (Cr, Cd, Cu, Mn, Ni, Pb and Zn) in soil and vegetables (Solanum lycopersicum and Daucus carota). The transfer of the trace elements from soil to vegetables and the potential risk assessment were studied as well. Results indicated relatively high levels of heavy metals. Cd, Cu and Pb exceeded the alert limits established by the Romanian legislation. Zn was high as well. Positive correlations between the Cr, Cu and Pb indicated similar source of pollution, possibly related to the activities occurred in the non-metallic facility, nearby the study area. The heavy metals determined in the Solanum lycopersicum fruits and Daucus carota roots were below the maximum allowable concentrations, according to the WHO/FAO guideline. Slightly higher amounts of Cr and Cu were measured in tomatoes, compared to the carrots. Nevertheless, carrots were richer in Ni and Mn. The applied pollution indices indicated a contamination with heavy metals in 90% of the soil samples, with 9% probability of toxicity, the remaining 10% being classified into the precaution domain category. The plant bioconcentration of heavy metals into the Solanum lycopersicum fruits and Daucus carota roots is characterized using transfer factors. Generally, the results indicate that Daucus carota was the most susceptible to uptake Cu and Mn, while Solanum lycopersicum would rather uptake Cd and Zn. The estimated non-carcinogenic risk, based on the human health risk indices, indicates that the studied vegetables are safe for consumption with no impact on the human health. The results are lower than the critical value. Similarly, the carcinogenic risk indices results showed acceptable risks of cancer developing. It is important to assess and monitor the heavy metals levels in soil and in the vegetables intended to be consumed, in order to prevent contamination and potential negative effects on the environment and implicitly on the human health. The obtained data can be used in remediation techniques, as well as in implementing control measures of heavy metal contamination in soil and vegetables.

Influence of Urban Informal Settlements on Trace Element Accumulation in Road Dust and Their Possible Health Implications in Ekurhuleni Metropolitan Municipality, South Africa

The study was aimed at assessing the influence of urban informal settlement on trace element accumulation in road dust from the Ekurhuleni Metropolitan Municipality, South Africa, and their possible health implications. The concentration of major and trace elements was determined using the wavelength dispersive XRF method. The major elements in descending order were SiO₂ (72.76%), Al₂O₃ (6.90%), Fe₂O₃ (3.88%), CaO (2.71%), K₂O (1.56%), Na₂O (0.99%), MgO (0.94%), MnO (0.57%), TiO₂ (0.40%), and P₂O₅ (0.16%), with SiO₂ and P₂O₅ at above-average shale values. The average mean concentrations of 17 trace elements in decreasing order were Cr (637.4), Ba (625.6), Zn (231.8), Zr (190.2), Sr (120.2), V (69), Rb (66), Cu (61), Ni (49), Pb (30.8), Co (17.4), Y (14.4), Nb (8.6), As (7.2), Sc (5.8), Th (4.58), and U (2.9) mg/kg. Trace elements such as Cr, Cu, Zn, Zr, Ba, and Pb surpassed their average shale values, and only Cr surpassed the South African soil screening values. The assessment of pollution through the geo-accumulation index (Igeo) revealed that road dust was moderately to heavily contaminated by Cr, whereas all other trace elements were categorized as being uncontaminated to moderately contaminated. The contamination factor (CF) exhibited road dust to be very highly contaminated by Cr, moderately contaminated by Zn, Pb, Cu, Zr, and Ba, and lowly contaminated by Co, U, Nb, Ni, As, Y, V, Rb, Sc, Sr, and Th. The pollution load index (PLI) also affirmed that the road dust in this study was very highly polluted by trace elements. Moreover, the results of the enrichment factor (EF) categorized Cr as having a significant degree of enrichment. Zn was elucidated as being minimally enriched, whereas all other trace elements were of natural origin. The results of the non-carcinogenic risk assessment revealed a possibility of non-carcinogenic risks to both children and adults. For the carcinogenic risk, the total CR values in children and adults were above the acceptable limit, signifying a likelihood of carcinogenic risk to the local inhabitants. From the findings of this study, it can be concluded that the levels of trace elements in the road dust of this informal settlement had the possibility to contribute to both non-carcinogenic and carcinogenic risks, and that children were at a higher risk than the adult population.

Transfer of Potentially Toxic Elements in the Soil-Plant System in Magnesite Mining and Processing Areas

Mining activities, ore concentrations, and transport processes generate large amounts of pollutants, including hazardous elements, which are released into the environment. This work presents the results of experimental research aimed at evaluating the environmental risks of soil and plant contamination in two magnesite mining and processing areas in the Slovak Republic, and assesses the phytoremediation potential of dominant plant species. Eleven potentially toxic elements in the soil were investigated using X-ray fluorescence spectrometry (Cd, Pb, Cr, Zn, Cu, As, Ni, Mn, Mg, Fe) and atomic absorption spectrometry (Hg). In plants, potentially toxic elements were investigated using inductively coupled plasma mass spectrometry (Cu, As, Cd, Pb) and inductively coupled plasma atomic emission spectrometry (Cr, Zn, Mn, Mg). Selected soil parameters (pH, redox potential, and soil organic matter) were also investigated. Soil contamination was evaluated using environmental indices (geoaccumulation index—Igeo, enrichment factor—EF, contamination factor—Cf, degree of contamination—Cd). The phytoremediation potential of plants was evaluated using the bioconcentration factor (BCF) and the translocation factor (TF). The soil reaction in the studied areas indicated a strong alkalization of the soil. The soils in Jelšava-Lubeník were significantly contaminated with Cr, As, Mn, and Mg. The most significant enrichment based on the average values of EF was found to be in the order of Cd > Mg > Zn > Cu > As > Cr > Ni > Pb > Fe > Hg > Mn. The observed values of Cf and Cd indicated a high degree of soil contamination. In Košice, the soils were found to be significantly contaminated with Cr, Mn, Mg, and Ni. The most significant enrichment was found in the order of Cd > Mn > Ni > Pb > Zn > Mg > Cu > As > Fe > Cr > Hg. Very high Cf was found for Pb and Cr. The results of correlation and hierarchical cluster analyses suggest a similar origin of pollutants caused by significant anthropogenic interventions due to magnesite mining and processing. The investigated dominant plant species, Phragmites australis, Agrostis stolonifera, Elytrigia repens, and Taraxacum officinale are able to accumulate high concentrations of the monitored potentially toxic elements without more serious load or damage. The results of BCF and TF confirmed that P. australis and T. officinale appeared to be suitable accumulators in the phytoextraction process. In the case of E. repens and A. stolonifera it was confirmed that they accumulate and immobilize high concentrations of potentially toxic elements, especially in the roots, establishing the suitability of their use in phytostabilization processes.

Soil contamination and health risk assessment from heavy metals exposure near mining area in Bac Kan province, Vietnam

Mining activities in Vietnam have resulted in potential heavy metals contamination, which unfavorably influences soil quality and represents a risk to human health. This study was designed to investigate the heavy metals contamination in the vicinity of the Pb-Zn and Au mines. Soil samples were collected along the stream, and then, solutions were prepared by a modified Aqua Regia method. They were analyzed by ICP-MS for trace elements, and the analytical result data of 7 elements (As, Cd, Co, Cu, Ni, Pb, and Zn) were used to define pollution indices with statistical results and to interpret the health risk assessment. For the preliminary identification of the pollution sources near the Pb-Zn mine of the elements, statistical analysis (including principal component analysis and Spearman correlation coefficient) and information about mineral composition ore and surrounding rocks were applied. The analytical results of heavy metals showed that the average concentrations of As and Pb were higher than the Vietnam standard for residential soil by about eight and three times, respectively. Pollution indices also indicated that Pb and As were the highest contamination factors in the soil near Pb-Zn mine and Au mine, respectively. Statistical analysis results revealed that the pollution sources of these elements in the soil near the Pb-Zn mine were a combination of anthropogenic and geogenic sources. Health risk assessment pointed out that children were at higher risk than adults in both non-carcinogenic and carcinogenic risk.

The protective role of MdATG10-mediated autophagy in apple plant under cadmium stress

Autophagy is a conserved degradation pathway in plants, which plays an important role in plant cellular homeostasis during abiotic stress. Although various abiotic stressors have been reported to induce autophagic activity in plants, the specific role of autophagy in plant cadmium (Cd) tolerance remains undiscovered. In this study, we treated three MdATG10-overexpressing apple lines with hydroponic Cd stress and found the enhanced Cd tolerance in transgenic plants. Transgenic apple plants exhibited less growth limitation and reduced Cd damage on the photosynthetic system. That was accompanied by higher antioxidant enzymes activity and lower harmful ROS accumulation in apple leaves under Cd stress. The higher autophagic activity led to a more active metabolic system of Pro, His, and Arg in transgenic plants under Cd stress, which was closely related to the plant Cd tolerance. In addition, the transcriptional activities of several Cd transport and detoxification-related genes were regulated by MdATG10-overexpression in response to Cd stress. This study is the first to demonstrate the protective role of autophagy in the Cd tolerance of plants.

Ecological evaluation of heavy metal pollution in the soil of Pb-Zn mines

Soil heavy metal pollution evaluations are a necessary measure for mine ecological control projects. In this study, the heavy metals Pb, Zn and Cd were studied in mining areas, tailings areas, sewage plant areas, residential areas, reclamation areas, and farmland areas. Soil pollution assessments of lead-zinc ore mine soils in the countryside of China are performed based on the index of geoaccumulation (I_geo) and the improved analytic hierarchy process (AHP). Finally, the pollution sources were analyzed by positive matrix factorization (PMF). The I_geo for the heavy metals Pb, Zn and Cd in the mining area reached 5.20, 3.34, and 5.66, respectively. In addition, 80 and 65% of the mining area and tailings area reached extremely strong pollution, respectively. The numerical simulation predicts that the pollution hazard in the southeast of the mine is high and that the pollution is concentrated. The severity of soil pollution in mines derived by the index of improved analytic hierarchy process (P_AHP) was as follows: mining area (70.80) > sewage plant area (35.57) > tailings area (30.64) > farmland area (28.40) > residential area (21.11) > reclamation area (10.06). Among the three categories of pollution sources, one includes reclamation area, farmland area and tailings area; one includes sewage plant area and residential area; and one includes mining area. The source contribution of Pb by the phenomenon of indiscriminate discharge of wastewater after ore smelting was as high as 90.4%; The contribution of the blind mining and tailings piling phenomenon of mines to the source of heavy metals Zn and Cd was 81.4 and 90.2%, respectively. This study proposes a reliable scientific method and technical method for evaluating mine soil pollution and provides a guiding basis for mine development and protection.

Assessment of Contents and Health Impacts of Four Metals in Chongming Asparagus-Geographical and Seasonal Aspects

In this paper, the contents of four typical metals (Pb, Cd, Hg, and As) in asparagus, water, and soil from Chongming Island were quantitatively determined by inductively coupled plasma mass spectrometry (ICP-MS). The contents of these metals in asparagus showed a common rule of Pb > As > Cd > Hg in different harvest seasons and regions. Significant seasonal differences were found in the contents by difference analysis, but no obvious regional differences were observed. Furthermore, the asparagus did not accumulate these four metals from the soil in Chongming Island by the assessment of bio-concentration factor. The asparagus was proved safe by the analysis of single-factor pollution index and Nemerow pollution index. Through combining the analysis of the above indexes and the geological accumulation index, we found that 51.62% of soil samples were mildly polluted by cadmium. The results of health risk analysis showed that the risk value of children was higher than that of adults under oral exposure, but the four metals in asparagus possessed no obvious risk to health. The above assessments illustrate that the daily consumption of asparagus in Chongming Island will not cause potential health impacts. It is of benefit to ensure the quality and economic interests of asparagus planting in Chongming Island through the investigation of this study.

Analysis and assessment of heavy metal contamination in the vicinity of Lake Atamanskoe (Rostov region, Russia) using multivariate statistical methods

Assessment of spatial patterns of potentially toxic metals is one of the most urgent tasks in soil chemistry. In this study, descriptive statistics and three methods of multivariate statistical analysis, such as the hierarchical cluster analysis (HCA), correlation analysis, and conditional inference tree (CIT), were used to identify patterns and potential sources of heavy metals (Co, Ni, Cu, Cr, Pb, MnO, and Zn). The investigation was carried out on 81 sample points, using 20 testing parameters. A strong positive correlation found among Ni, Cu, Zn, and HCA results has confirmed the common origin of the elements from waste discharge. Hierarchical CA divided the 81 test sites into 5 classes based on the soil quality and HMs contamination similarity. Regression trees for Cr, Pb, Zn, and Cu were verified by the splitting factor including HMs content and soil chemistry factors. The CIT has revealed that the elements (Cr, Pb, Zn, and Cu) concentration values are split at the first level by some other metal, indicating common anthropogenic impact resulting from industrial waste discharges. The factors at the next hierarchical level of splitting, in addition to the HMs, include compounds belonging to soil chemistry variables (SiO₂, Al₂O₃, and K₂O). The CIT nonlinear regression model is in good agreement with the data: R² values for log-transformed concentrations of Cr, Pb, Zn, and Cu are equal to 0.775; 0.774; 0.775; 0.804, respectively.

AMPK/PPAR-γ/NF-κB axis participates in ROS-mediated apoptosis and autophagy caused by cadmium in pig liver

The experiment was conducted to investigate the effects of Cadmium (Cd) on growth performance, blood biochemical parameters, oxidative stress, hepatocyte apoptosis and autophagy of weaned piglets. A total of 12 healthy weaned piglets were randomly assigned to the control and the Cd group, which were fed with a basal diet and the basal diet supplemented with 15 ± 0.242 mg/kg CdCl₂ for 30 d, respectively. Our results demonstrated that Cd significantly decreased final body weight, average daily feed intake (ADFI), average daily gain (ADG) and increased feed-to-gain (F/G) ratio (P < 0.05). For blood biochemical parameters, Cd treatment significantly decreased the red blood cell (RBC), hemoglobin (HGB), hematocrit (HCT), total protein, albumin, copper content and iron content (P < 0.05). In addition, liver injury was observed in the Cd-exposed group. Our results also demonstrated that Cd exposure contributed to the production of ROS, activated the AMPK/PPAR-γ/NF-κB pathway (increasing the expressions of P-AMPK/AMPK, NF-κB, I-κB-β, COX-2, and iNOS, decreasing the expressions of PPAR-γ and I-κB-α), finally induced autophagy (increasing the expressions of Beclin-1, the ratio of LC3-II/LC3-I and p62), and apoptosis (increasing the expressions of Bax, Bak, Caspase-9, and Caspase-3, decreasing the expression of Bcl-2). Overall, these findings revealed the vital role of AMPK/PPAR-γ/NF-κB pathway in Cd-induced liver apoptosis and autophagy, which provided deeper insights into a better understanding of Cd-induced hepatotoxicity.

Source, degree and potential health risk of metal(loid)s contamination on the water and soil in the Söke Basin, Western Anatolia, Turkey

Water and soil quality are the two most important parameters for sustainable agriculture and regional development in the basin. This study focused on the causes of soil and water contamination and the potential impact of drinking water on community health. Reasons for metal(loid)s enrichment in the water and soil in the Söke Basin were examined by considering anthropogenic and geogenic inputs. Four rock samples in the drainage network, 28 soil samples, and 29 water samples in the Söke Plain were collected. All samples were analyzed for metal(loid)s by inductively coupled plasma-mass spectrometry (ICP-MS). The carcinogenic and non-carcinogenic effects of water on human health were calculated mathematically. Potential ecological risk index (PERI), enrichment factor (EF), and ecological risk (ER) were calculated for the soil samples. In addition, principal component analysis (PCA) with Varimax rotation and Kaiser normalization was applied to the soil data set. Cr, Ni, and Cd contamination in soils was associated with anthropogenic inputs, while arsenic contamination was related to both anthropogenic and geogenic inputs. As, B, Ba, Pb, and Sb contamination was found in some drinking water. As contamination has been clearly found to be caused by natural geological processes in and around Lake Azap. It was determined that metal(loid)s enrichment occurred in drinking water due to the mixing of geothermal waters affected by seawater intrusion with surface and groundwater. Contamination inputs were geogenic, but their negative impacts appearing in surface water and drinking water occurred due to human influence.

Evaluation of nitrogen and heavy metal pollution in southern Caspian Sea: Risk assessment and modeling approach

Industrial, agricultural, and recreational activities dump several pollutants into the Caspian Sea, which is one of the main water bodies of Iran. Therefore, performing risk assessments would be required as part of the monitoring programs. Herein, non-cancer health risk assessment of the consumption of macroalgae was performed and the ecological risk assessment of metal pollution in sediments of the southern Caspian Sea was presented using sediment quality guidelines (SQGs), enrichment factors (EF), contamination factors (CF), contamination degrees (CD), pollution load indices (PLI), geo accumulation indices (I_geo), and potential ecological risk indices (RI). Next, machine-learning approaches were used to predict the stable isotope value of nitrogen in macroalgae, in which physicochemical information of water and heavy metal levels in macroalgae were used separately and together as predictor variables. Results indicated that simultaneous use of physicochemical properties of water and heavy metal levels resulted in the best prediction of isotopic nitrogen content.

Soil Contamination in the Problem Areas of Agrarian Slovakia

Landfills, old and abandoned mines, industrial sites, heaps, sludge ponds and other sources of pollution represent environmental threats and are characterized as chemical time bombs. This work is focused on the evaluation of soil contamination by risk elements using various indices (geoaccumulation index—Igeo, enrichment factor—EF, contamination factor—Cif and degree of contamination—Cd). These selected agrarian problem areas are located in Slovakia, especially in the air pollution field of landfills consisting of power plant fly ash, tannery and footwear wastes, leachate (lúženec), iron ore slag, waste from metallurgy and sludge ponds in which coal sludge waste is deposited and waste from ore treatment. Nine research sites in the agrarian region of Slovak Republic were monitored. Ten risk elements (Fe, Mn, Zn, Cu, Co, Ni, Cr, Pb, Cd and Hg) and pH/H2O were included in this study and were determined in surface soils (of 0.05 m to 0.15 m) using atomic absorption spectrometry (AAS). Our study showed the highest exceedance of the limit values of risk elements in the order Ni (51.85 times) > Co (25.47 times) > Cd (13.70 times) > Cu (12.78 times) > Cr (8.37 times) > Fe (8.26 times) > Hg (7.94 times) > Zn (5.71 times) > Pb (4.63 times). The content of risk elements increased based on the average values of Igeo in the order of Cr < Hg < Zn < Pb < Ni < Cu < Cd. Igeo values for cadmium indicated mild-to-extreme contamination at all sites. We found the most significant enrichment in the order of Cd > Cu > Pb > Ni > Zn > Hg > Cr. EF values for cadmium indicated extremely high enrichment; the Cif and Cd values indicated a very high degree of soil contamination near the nickel smelter landfill, an industrial metallurgical plant and old but active mines. The studied areas pose a serious danger not only to the soil but also to groundwater and biota due to the prevailing low soil reaction, which increases the mobility of toxic elements. The study provides important results for the development of effective strategies for the control and remediation of endangered areas.

Environmental health survey for children residing near mining areas in South Gobi, Mongolia

Background

We evaluated the level and factors of heavy metal exposure to children residing in the Togttsetsii, Khanbogd, and Bayandalai soums of South Gobi province, Mongolia.

Methods

A total of 118 children aged 9–12 years were surveyed, and the level of heavy metal exposure in their bodies was investigated. Exposure was investigated by measuring concentrations of heavy metals such as cadmium, lead, and mercury in the blood; mercury concentration in the hair; and total arsenic in the urine.

Results

Blood cadmium concentration had geometric averages of 0.16 µg/L in the children from Bayandalai, 0.15 µg/L Tsogttsetsii, and 0.16 µg/L Khanbogd. Blood lead concentration showed a relatively higher geometric average of 7.42 µg/dL in the children from Bayandalai compared to 4.78 µg/dL and 5.15 µg/dL in those from Tsogttsetsii and Khanbogd, respectively. While blood mercury concentration was the highest in the children from Bayandalai, with a value of 0.38 µg/L, those from Tsogttsetsii and Khanbogd had similar concentrations of 0.29 µg/L and 0.29 µg/L, respectively. Hair mercury concentration was the highest in the children from Bayandalai, with a value of 78 µg/g, a particularly significant difference, with a concentration of 0.50 µg/g in those from Khanbogd. Urine arsenic concentration was the highest in the children from Khanbogd, with a value of 36.93 µg/L; it was 26.11 µg/L in those from Bayandalai and 23.89 µg/L in those from Tsogttsetsii.

Conclusions

The high blood lead concentration of children in Bayandalai was judged to be due to other factors in addition to mine exposure; the reason why blood and hair mercury concentration was higher in children from Bayandalai may have been due to exposure to many small-scale gold mines in the area. In the case of Khanbogd, it was estimated that the high arsenic level in urine was caused by the effect of mines.

Multi-element contamination in soils from major mining areas in Northeastern of Brazil

Mining has become one of the main factors in the global biogeochemical cycle of potentially toxic elements. Therefore, it is considered one of the anthropogenic activities with the greatest negative impact on the environment. These impacts are maximized in semiarid regions, where mining activities can lead to soil degradation and decrease in land productivity. This study aimed to assess the level of contamination in natural, urban, and agricultural soils of three important mining areas, where approximately 80,000 people live, and pollution levels have never been determined before. For this purpose, soil samples were collected around iron, uranium, and vanadium mines, as well as in the main human settlements of the region. The concentrations of 34 elements were determined by instrumental neutron analysis activation (INAA) and inductively coupled plasma optical emission spectrometry (ICP OES) techniques. Pollution indices (CF, EF, mC_d, PLI, and REEP) revealed that there is a moderate to heavy level of pollution for 89% of the analyzed elements. Additionally, an extreme contamination level was observed in 78% of the samples, for at least one element. Statistical analyses were performed to identify patterns in the distribution and common sources of pollution. The results suggest that the concentrations for Al, Ba, Hf, Na, Pb, Rb, REE, Ta, Th, U, Zn, and Zr are associated with geogenic causes. However, the influence of anthropogenic sources such as agriculture and mining on the accumulation of these elements in soils should not be disregarded. In contrast, the contents of As, Br, Cd, Co, Cr, Cs, Cu, Fe, K, Mn, Ni, Sc, Ti, and V reflect the direct impact of anthropogenic sources.

Characteristics and health risk assessment of heavy metal contamination from dust collected on household HVAC air filters

Heavy metals associated with airborne particulate matter are detrimental to human health, but risk assessment is difficult due to the technical challenges of determining exposure rates. In houses and other buildings, the heating, ventilation and air conditioning (HVAC) system is equipped with an air filter that captures airborne particulate matter from the indoor air that enters the HVAC system. This study used the air filter dust as a proxy for the heavy metal exposure of children and adults, based on a household study in Kuwait. Air filter dust contained from 12.5 ± 5 mg Co/kg dust to 14 453 ± 5046 mg Fe/kg dust. Houses had high levels of Fe, Al, Zn, and Mn and relatively low concentrations of As and Co. Source apportionment revealed that metals in air filter dust were from natural and anthropogenic sources, including vehicular emissions, fossil fuel combustion, and metals-related industries. The total Hazard Index (HI; Σ exposure routes) for heavy metals was >1 for children and adults. Total cancer risks (TCR; Σ exposure routes) were 5.93 × 10^-3 (95% CI: 5.28 × 10^-3- 6.59 × 10^-3) for children and 5.16 × 10^-3 (95% CI: 4.59 × 10^-3 - 5.73 × 10^-3) for adults. Heavy metals, particularly the Cr and Pb concentrations, contribute to the non-carcinogenic and carcinogenic health risks of children and adults in Kuwait households.

Environmental Risk Assessment of Recycled Products of Spent Coppery Etchant in Jiangsu Province, China

With the vigorous development of the 5G industry, the characteristic hazardous waste, spent coppery etchant, was also produced in large quantities. In recent years, there are many companies that have begun to collect spent coppery etchant for the purpose of producing recycled products, such as copper sulfate, copper oxide, basic copper chloride, and copper powder, which often contain large amounts of heavy metals. However, due to the lack of relevant standards and applicable regulatory measures, some of the recycled products flow to the feed processing industry and even to the food processing industry. This study investigated the pollution status of heavy metals in recycled products of spent coppery etchant and evaluated the impact of recycled products exposure on human health. The results showed that the content of Zn was the highest, which was 21 times higher than the corresponding standard limit. Human health risk assessment indicated that the hazard quotients of As account for 87.5% of the entire HI value, while the average carcinogenic risk values of As for copper sulfate, copper oxide, basic copper chloride, and copper powder are 1.09 × 10⁻⁵, 3.19 × 10⁻⁵, 1.29 × 10⁻⁵, 7.94 × 10⁻⁶, respectively. Meanwhile, suggestions on the supervision of recycled products and the concentration limits of heavy metals in recycled products were put forward.

Mineralogy and geochemistry of clay fractions in soils developed from different parent rocks in Limpopo Province, South Africa

This study investigates the mineralogical and geochemical characteristics of clay fractions in soils developed from different parent rocks in Limpopo Province, South Africa using the X-ray diffraction (XRD), X-ray Fluorescence (XRF) Spectrometry, Laser Ablation - Inductively Coupled Plasma - Mass Spectrometry (LA-ICP-MS), Fourier Transform Infrared (FTIR) Spectrophotometry, Thermogravimetric Analysis and Differential Scanning Calorimetry (TGA-DSC) analytical techniques. Health risk associated with the presence of some trace elements was also investigated. The results revealed that the clay fractions had kaolinite as the dominant clay component occurring with other weatherable minerals. The crystallinity based on FTIR for the soil kaolinites correspond to partially - poorly ordered structures. The geochemical data showed appreciable accumulation of trace elements in the clay fractions. The absence of negative Ce anomaly in the chrondrite-normalised rare earth elements (REE) pattern in the clay fractions suggest the alteration of the primary minerals took place under suboxic conditions. The average non-carcinogenic hazard index (HI) were 1.52, 1.08, and 2.01 for children and 0.18, 0.13, and 0.24 for adults in the clay fractions from basalt, granite, and arkosic sandstone, respectively. The HI > 1 for children suggest non-carcinogenic health risk to children with ingestion pathway contributing the highest. The average carcinogenic risk index values were >10-3 for children and adults with respect to Cr, Ni, and Pb in the clay fractions. This suggests very high carcinogenic risk to children and adult population in decreasing order from clay fractions in arkosic sandsone > basalt > granite, respectively.

Research on the Mechanisms of Plant Enrichment and Detoxification of Cadmium

The heavy metal cadmium (Cd), as one of the major environmentally toxic pollutants, has serious impacts on the growth, development, and physiological functions of plants and animals, leading to deterioration of environmental quality and threats to human health. Research on how plants absorb and transport Cd, as well as its enrichment and detoxification mechanisms, is of great significance to the development of phytoremediation technologies for ecological and environmental management. This article summarises the research progress on the enrichment of heavy metal cadmium in plants in recent years, including the uptake, transport, and accumulation of Cd in plants. The role of plant roots, compartmentalisation, chelation, antioxidation, stress, and osmotic adjustment in the process of plant Cd enrichment are discussed. Finally, problems are proposed to provide a more comprehensive theoretical basis for the further application of phytoremediation technology in the field of heavy metal pollution.

HERisk: An improved spatio-temporal human health risks assessment software

Risk assessment is considered an essential tool to assist in the management and mitigation of polluted areas, especially those associated with economic activities that significantly degrade the environment, such as mining. However, most of the methodologies of risk assessment adopt the deterministic approach of using a fixed value for ascertaining the hazards derived from exposure to chemical pollutants. However, this is not the case of the Human, Ecological and Radiological Risk (HERisk) code, which allows space-time assessments of ecological, radiological, and human health risks. Indeed, this work aims to describe this new software (enhanced version of HHRISK), which not only improves the performance of the code but also increases its applicability and versatility. To showcase its usefulness in evaluating ecological pollution and human health risk were studied the contents of potentially toxic elements (Co, Cu, Fe, Mn, Ni, Pb, and Zn) in soils and surface waters from the nickel mining area in the municipality of Itagibá (Bahia, Brazil). The obtained results showed that metals are non-homogeneous distributed, suggesting the presence of local enrichment sources, mainly related to human activities. The statistical analyses carried out revealed that mining and agricultural activities are possibly responsible for the contents of these pollutants in both soils and surface waters. The calculated ecological indices of pollution confirmed anthropogenic pollution around the mining area, especially in the locations closest to sterile waste piles. The results of the human health risk assessment revealed that the ingestion of meat and contaminated water are the main routes for entering the potentially toxic elements to the human body and that Co is the chemical specie that poses the highest risk in the entire region. The hazard index (HI) values indicated that the whole area around the mine should be considered as a high risk for human health.

Analysis of Heavy Metal Content in Soil and Plants in the Dumping Ground of Magnesite Mining Factory Jelšava-Lubeník (Slovakia)

A high content of heavy metals in the soil and plants of a magnesite mining area might cause serious damage to the environment and can be a threat to the health of the surrounding population. This paper presents the results of research that focused on analyzing the heavy metal content in soil and plants in the dumping grounds of the magnesite mining factory Jelšava-Lubeník (Slovakia). The analysis focused on the content of heavy metals in soil (X-ray fluorescence spectrometry, atomic absorption spectrometry), in plants (inductively coupled plasma mass spectrometry, inductively coupled plasma atomic emission spectrometry), and pH (1M KCl solution). The results showed that the soil in the study area was slightly acidic to strongly alkaline and the content of Cr, As, Mn, and Mg exceeded by several times the limit values for the Slovak Republic. The results of the hierarchical cluster analysis and the correlation analysis show that the grouped metals come from the same sources of pollution. The content of heavy metals in plants was high and the highest concentration was found in the roots of Elytrigia repens > Agrostis stolonifera > Phragmites australis and flowers of Phragmites australis. The findings confirmed the suitability of the used plants in the process of phytoextraction and phytostabilization. The acquired knowledge can help in planning and realization remediation measures and improve the state of the environment in areas exposed to magnesite mining.

Analysis of Spatial Variability of River Bottom Sediment Pollution with Heavy Metals and Assessment of Potential Ecological Hazard for the Warta River, Poland

Pollution of river bottom sediments with heavy metals (HMs) has emerged as a main environmental issue related to intensive anthropopressure on the water environment. In this context, the risk of harmful effects of the HMs presence in the bottom sediments of the Warta River, the third longest river in Poland, has been assessed. The concentrations of Cr, Ni, Cu, Zn, Cd, and Pb in the river bottom sediments collected at 24 sample collection stations along the whole river length have been measured and analyzed. Moreover, in the GIS environment, a method predicting variation of HMs concentrations along the whole river length, not at particular sites, has been proposed. Analysis of the Warta River bottom sediment pollution with heavy metals in terms of the indices: the Geoaccumulation Index (Igeo), Enrichment Factor (EF), Pollution Load Index (PLI), and Metal Pollution Index (MPI), has proved that, in 2016, the pollution was heavier than in 2017. Assessment of the potential toxic effects of HMs accumulated in bottom sediments, made on the basis of Threshold Effect Concentration (TEC), Midpoint Effect Concentration (MEC), and Probable Effect Concentration (PEC) values, and the Toxic Risk Index (TRI), has shown that the ecological hazard in 2017 was much lower. Cluster analysis revealed two main groups of sample collection stations at which bottom sediments showed similar chemical properties. Changes in classification of particular sample collection stations into the two groups analyzed over a period of two subsequent years indicated that the main impact on the concentrations of HMs could have their point sources in urbanized areas and river fluvial process.

A review on phytoremediation of contaminants in air, water and soil

There is a global need to use plants to restore the ecological environment. There is no systematic review of phytoremediation mechanisms and the parameters for environmental pollution. Here, we review this situation and describe the purification rate of different plants for different pollutants, as well as methods to improve the purification rate of plants. This is needed to promote the use of plants to restore the ecosystems and the environment. We found that plants mainly use their own metabolism including the interaction with microorganisms to repair their ecological environment. In the process of remediation, the purification factors of plants are affected by many conditions such as light intensity, stomatal conductance, temperature and microbial species. In addition the efficiency of phytoremediation is depending on the plants species-specific metabolism including air absorption and photosynthesis, diversity of soil microorganisms and heavy metal uptake. Although the use of nanomaterials and compost promote the restoration of plants to the environment, a high dose may have negative impacts on the plants. In order to improve the practicability of the phytoremediation on environmental restoration, further research is needed to study the effects of different kinds of catalysts on the efficiency of phytoremediation. Thus, the present review provides a recent update for development and applications of phytoremediation in different environments including air, water, and soil.