Concentrations Of Toxic Elements Research Articles

Co-occurrence and correlation of arsenic, cadmium, and lead in processed foods intended for infants and young children: evaluation of two statistical approaches adapted to censored data and their implications for risk management

We evaluated the co-occurrence of arsenic (As), cadmium (Cd), and lead (Pb) in 10 categories of processed foods intended for infants and young children (<2 years old) and adapted methodology to characterise and evaluate the impact of correlations on toxic element (TE) concentrations in these foods. Co-occurrence was assessed by calculating the frequency of samples having concentrations above the limit of detection (LOD) among TE sets (i.e. As-Cd, As-Pb, Cd-Pb, and As-Cd-Pb). Pairwise correlations were evaluated using two statistical approaches adapted to censored data: (i) non-parametric Kendall’s tau and (ii) parametric Bayesian modelling. Nonparametric and parametric correlation analyses showed similar results. We found positive correlations among one or more pairs of the TEs (As, Pb, and Cd) in 9 of the 10 categories of foods intended for infants and young children and a negative correlation for one TE pair for a single food category. Where positive correlations are observed, removing samples with high concentrations of a given TE reduces the mean of the other TEs in that food. We also explored the impact of correlations among TEs on the fraction of the supply below maximum levels. Positive correlations among TEs have the potential to reduce the impact on the supply when setting multiple maximum levels.

Human biomonitoring of essential and toxic trace elements (heavy metals and metalloids) in urine of children, teenagers, and young adults from a Central European Cohort in the Czech Republic.

Exposure to toxic trace elements, which include metals and metalloids, can induce adverse health effects, including life-threatening diseases. Conversely, essential trace elements are vital for bodily functions, yet their excessive (or inadequate) intake may pose health risks. Therefore, identifying levels and determinants of exposure to trace elements is crucial for safeguarding human health. The present study analyzed urinary concentrations of 14 trace elements (arsenic, cadmium, cobalt, chromium, copper, mercury, manganese, molybdenum, nickel, lead, antimony, selenium, thallium, and zinc) and their exposure determinants in 711 individuals, spanningfrom children to young adults from a Central European population from the Czech Republic. Multivariate linear regression and non-parametric Kruskal-Wallis ANOVA were used to investigate exposure determinants. Estimates of 95th percentile concentrations and confidence intervals were carried out to establish reference values(RV95). The study also assessed the percentage of population exceeding health-based guidance values (GVs) to gauge health risks. Young adults showed elevated toxic element concentrations, whereas children exhibited higher concentrations of essential elements. Mercury concentrations were associated with both dental amalgam filling count and seafood intake; arsenic concentrations were associated with seafood, rice, and mushroom consumption. Mushroom consumption also influenced lead concentrations. Sex differences were found for cadmium, zinc, nickel, and cobalt. Between 17.9% and 25% of the participants exceeded recommended GV for arsenic, while 2.4% to 2.8% exceeded GV for cadmium. Only one participant exceeded the GV for mercury, and none exceeded GVs for chromium and thallium. Essential trace elements' GVs were surpassed by 38% to 68.5% participants for zinc, 1.3% to 1.8% for molybdenum, and 0.2% to 0.3% for selenium. The present study examines trace element exposure in a Central European population from the Czech Republic, unveiling elevated exposure levels of toxic elements in young adults and essential elements in children. It elucidates key determinants of trace element exposure, including dietary and lifestyle indicators as well as dental amalgam fillings. Additionally, the study establishes novel reference values and acomparison with established health-based human biomonitoring guidance values, which are crucial for public health decision-making. This comprehensive biomonitoring study provides essential data to inform public health policies and interventions.

Human Exposure through the Diet to Arsenic and Other Toxic Elements: A Literature Review of Scientific Studies Conducted in Catalonia, Spain, in the Current Century.

Human exposure to arsenic and other toxic elements such as cadmium, lead and mercury may lead to a wide range of adverse health effects. In relation to this, it is well established that the diet is the main route of exposure to both essential and toxic trace elements. In recent years, the levels of toxic elements in foodstuffs have been measured in numerous studies conducted all over the world. Scientific databases show that, in the current century, China and Spain have been the countries where the most surveys on this topic have been carried out. Regarding Spain, Catalonia is the region where most studies aimed at determining the concentrations of trace elements in food have been performed. The objective of this paper was to review the studies carried out in Catalonia on the concentrations of As and toxic metals (including Cd, Hg and Pb) in food, as well as their estimated dietary intakes (EDIs). The results of total diet studies (TDSs) and duplicate diet (DD) studies have been included. For most toxic elements, a continued reduction in the EDI has been observed. This reduction is associated with a decrease in their concentrations in food, and with certain changes in dietary habits. Fish and seafood is the food group showing the highest content of toxic elements. However, none of the adult groups exceeded-in general-the safety thresholds for As, Cd, Hg and Pb established by the European Food Safety Agency (EFSA).

The Effect of Radionuclide and Chemical Contamination on Morphological and Anatomical Parameters of Plants

This article presents the results of a study of the influence of radionuclide and chemical pollution on the morphological and anatomical parameters of Calamagróstis epigéjos plants growing in the territory of “Degelen” at the Semipalatinsk Test Site (STS). Quantitative data of morphological and anatomical parameters are given, and the content of radionuclides and toxic elements in samples of plants obtained. Statistical processing of the obtained data was conducted. The results revealed that elevated concentrations of radionuclides 137Cs and 90Sr, and the calculated absorbed dose, do not have effects on plants. Changes in the anatomical parameters of leaves and stems were observed at elevated concentrations of the elements: for leaves—Al, Pb, Sr, U, Ni, Rb, Sm; for stems—Al, Cr, Cd, U, Cu, Be, Ni, Sm, Fe. The mesophyll of the leaves and the epidermis of the stems were the most exposed to toxic elements. The data of the anatomical parameters are recommended to be used as indicative parameters of plants grown in chemically contaminated areas.

High-yield rice with rich nutrition and low toxicity can be obtained under potato-rice cropping system.

Rice is often rotated with dryland crops to produce sufficient foodstuff, as rice is the main food crop of humans. In order to verify whether under the intensive rice-based cropping system, high yield and good quality of rice can be achieved simultaneously to ensure food security. Five long-term paddy-upland rotations - wheat-rice (WR), rapeseed-rice (RR), garlic-rice (GR), broad beans-rice (BR) and potato-rice (PR) - were conducted from 2014 to investigate rice yield, along with the profiling of 24 elements in rice grain. Mg, Zn, Cu, As, Mo and Sb concentrations were highest in the aleurone layer, and Ag and Cd concentrations showed little variation among different parts of the rice grain. Al, Ti, V, Si, Fe and Tl concentrations in the endosperm under GR were higher, while the Se concentration under PR was the highest. Furthermore, the yield of GR and PR were higher than the other three rotations with N supplementation, and the sustainable yield index of PR and WR were larger than 0.8. When we consider the concentration of toxic (As, Cd and Pb) and nutrient elements (Ca, Fe, Zn, Se, Cu and Mg) in the endosperm and grain yields, PR can simultaneously achieve high yield, high nutrition and low toxicity with different nitrogen treatments. Here we provide novel insights regarding the selection of rice-based cropping systems, focused on producing nutritious and safe rice with high grain yield. © 2024 Society of Chemical Industry.

Microplastic Abundance, Characteristics, and Heavy Metal Contamination in Coastal Environments of Western Sri Lanka

This study was conducted to assess the abundance of microplastics and associated metal contamination from selected beaches in the Western Province of Sri Lanka. Beach sand samples were collected from four beaches: Modera, Negombo, Mount Lavinia, and Panadura. Microplastics were extracted from dried sand samples using a saturated NaCl solution and sieved. Particles were identified using Fourier Transform InfraRed spectrophotometer, and associated heavy metals; Cr, Pb, Cu, Zn, and Ni were subjected to acid digestion for 24 hours before analysis using Microwave Plasma Atomic Emission spectrometry. More than half of the extracted plastics (56.31%) were identified as microplastics. The average microplastic abundance in beach sand samples ranged from 42.0-91.3 items/kg. The lowest and highest abundances were reported from the sand collected at Mount Lavinia and Panadura beaches, respectively. Hydrodynamic factors like ocean currents, wave patterns, associated Southwest monsoon period, and human activities may have caused the variability in microplastic abundances and metal contamination. The majority of the microplastics (52.29%) were polyethylene, whereas the second most abundant microplastic type was polypropylene (35.18%), resembling the records of the most common plastic waste types in the country. The majority of microplastics were fragments (87.95%) while white was the prominent color (53.49%). The toxic trace element concentration ranged from 5.0×10-3 to 1.8×102 μg/g in beaches. Furthermore, this study establishes a baseline for the west coastline prior to the X-press Pearl Ship Disaster in 2021. Future studies are encouraged to assess the beach microplastic pollution across the entire Sri Lankan coastline.

Токсичные и биогенные элементы в органах и тканях белой куропатки (Lagopus lagopus L., 1758) на севере Красноярского края (обзор)

Studying the concentration of biogenic and toxic microelements in the body tissues of wild animals is relevant for organizing regional environmental monitoring, assessing the state of populations and ensuring the safety of meat and wild products. The studies were carried out to determine the content of biogenic and toxic elements in the organs and tissues of the willow ptarmigan in the north of the Krasnoyarsk Region, Russia, where different levels of technogenic pollution are expected. The iron, copper, nickel, lead, and cadmium content in the pectoral muscles and liver of willow ptarmigan (Lagopus lagopus L.) (n=162), bagged during five hunting seasons in 2005–2019, were determined using atomic absorption spectrometry. The levels of lead, cadmium and iron in the tissues were significantly higher in contaminated areas, while the copper levels did not differ. Element concentrations in liver and skeletal muscle in impact areas were highly correlated with each other. This may be related to common sources of pollutant emissions. Sex differences in micronutrient content can be determined by spatial differentiation of the sexes during migration, seasonal feeding patterns, and the specific birds’ metabolism in reproductive period. Cadmium and lead content in liver and muscle tissue samples from impact areas exceeded current food hygiene standards, which may pose a threat to consumers. Probably, high levels of lead and cadmium reflect the increased content of metals in food items primarily willow sprouts and buds, which are the most important winter food for ptarmigan.

Origin, distribution, fate, and risks of potentially toxic elements in the aquatic environment of Bengaluru Metropolis, India

This study probes the water quality, including pH, total dissolved solids (TDS), and potentially toxic elements (PTEs) concentrations, and the associated environmental and human health implications, in forty one surface water bodies in Bengaluru metropolis, southern India. The pH in 54%, TDS in 63%, Ni in 12%, and U, Mo, Pb, Cr, Co, and Cu in 5% of the forty one water bodies exceed the WHO’s permissible limits for drinking purpose. Total dissolved solids display a significant positive correlation with Pb, Cr, Co, Cu, and Ni, suggesting the association of these elements with particulate matter. Sources of metal pollution include industries in the city's west (high levels of Pb, Cr, Co, Ni, and Cu), traffic in the city Centre (Mo), and geogenic (U) sources in the city's north, east, and south. The degree of contamination is high in 25%, moderate in 10%, and low in 65% of the forty one water bodies, with the highest degree of contamination in Narasappanehalli Lake in the industrial zone, Deepanjali Nagara Lake, and Govindraj Nagar drainage systems. Uranium, Pb, and Mo display a low to medium degree of contamination, whereas Cr, Co, Ni, and Cu display a medium to high degree of contamination. The non-carcinogenic risk through ingestion of contaminated water is medium to high for adults and children and the carcinogenic risk is high in all water bodies. Channels transport contaminated water from Bengaluru water bodies to the Pinakani and Cauvery Rivers and then to the northern Indian Ocean. The states of Karnataka and Tamil Nadu rely on water from these rivers for domestic and agricultural use exposing large populations to contaminated waters. Additionally, contaminated waters can negatively impact flora and fauna of Peninsular India as well as the marine biota of the northern Indian Ocean.

Green tech soil analysis: a comparison of potentially toxic element contents among urban, agricultural, and gold mining areas in the Eastern Brazilian Amazon.

Artisanal gold mining can lead to soil contamination with potentially toxic elements (PTEs), necessitating soil quality monitoring due to environmental and human health risks. However, determining PTE levels through acid digestion is time-consuming, generates chemical waste, and requires significant resources. As an alternative, portable X-ray fluorescence (pXRF) offers a faster, more cost-effective, and sustainable analysis. This study compared total As, Ba, Cr, Cu, Fe, Mn, Ni, Pb, Sr, Ti, V, and Zn obtained from pXRF with their pseudo-total contents obtained through acid digestion (USEPA method 3051A) in areas influenced by artisanal gold mining in the Eastern Amazon, Brazil. pXRF data and machine learning algorithms were used to predict extractable Cu, Fe, Mn, and Zn. Linear regression models were fitted to compare the two methods, and random forest and support vector machine techniques were used to predict extractable contents. The best regression model fits for the pseudo-total PTE contents were those for Cu, Fe, Mn and Pb in agricultural areas (R2 > 0.80); Fe and Mn in gold mining residue (R2 > 0.70); and Ba, Cu and Mn in urban areas (R2 > 0.80). The best models for predicting the extractable PTE contents were those for Cu (R2 = 0.72; RMSE = 2.58mgdm-3) and Zn (R2 = 0.71; RMSE = 1.44mgdm-3) in agricultural areas and for Zn (R2 = 0.72; RMSE = 0.43mgdm-3) in gold mining residue. The results demonstrated that pXRF can characterize and predict PTE contents in mining-impacted areas, offering a sustainable approach to soil quality analysis.

Contextualizing toxic elements in the diet: a case for integration of toxic element data into food databases.

Food composition data plays a key role in the practice of nutrition. However, nutrition professionals may currently lack the resources they need to integrate information about toxic elements - such as arsenic, cadmium, and lead - in food into the advice they give consumers. Geographic, sociocultural, and individual factors may impact not only the toxic element content of food, but also how the balance between potentially toxic and health-promoting components of food must be weighed. Better integration and contextualization of toxic element data into key food databases could allow for more nuanced, comprehensive nutrition guidance.

Sanitary and Chemical Analysis of Drinking Water and Laboratory Control of the Content of Toxic Elements of Pesticides and Mycotoxins in Food Products

Relevance of the study: nutrition is the most important factor in maintaining health, normal growth and development of children and adolescents, preventing a number of diseases, maintaining high performance of the adult population, maintaining active longevity. Drinking water and food are necessary for the existence of humans and all life on Earth. Issues related to increasing responsibility for the effectiveness and objectivity of quality control of drinking water and food products are relevant in guaranteeing their safety for the health of consumers. Objectives of the study: to study the quality of drinking water and the efficiency of the water supply system in Osh in the period from 2020 to 2023; analysis of compliance of drinking water quality with sanitary and chemical standards; development of recommendations for improving the quality of water and the water supply system in Osh. Determination of toxic elements, pesticides and mycotoxins in food products, determination of physicochemical indicators and toxic elements in drinking water, pesticides and mycotoxins in food products was carried out in accordance with regulatory documents of GOST and the maximum permissible concentration. The test results showed the normal and permissible levels of pH, total iron, fluorides, hardness, dry residue, ammonia, nitrates, etc. in water, and the content of aflatoxin B1, the mass concentration of cadmium and lead, hexachlorane, dichlorodiphenyltrichloroethane in food products. For a more in-depth analysis, it is recommended to use additional data on climatic conditions, geological features of the region, as well as the demographic situation in Osh.

P22-03 Concentrations of toxic elements in freshwater fish (Cyprinus carpio) blood and eggs: potential health implications

P22-03 Concentrations of toxic elements in freshwater fish (Cyprinus carpio) blood and eggs: potential health implications

Trace elements determination and health risk assessment of groundwater sources in Kumasi Metropolis, Ghana.

Trace element (TEs) contamination in groundwater is a key factor for health risk assessment and one of the environmental challenges linked with Ghana's sustainable development. This study aims to investigate TE concentrations in groundwater used for drinking and domestic purposes and their potential health risk in the Kumasi Metropolis using multivariate statistics. In the study, 23 groundwater samples were analyzed for 32 TEs using Perkin Elmer Nexion 2000 Inductively Coupled Plasma Mass Spectrometer (ICP-MS). Levels of TEs recorded in the study were in order of Na > Si > Ca > K > Mg > S > Ba > Cu > Zn > Al > Sr > Li > Mn > P > Fe > B > Pb > Ni > Co > Bi > Se > Sb > Cr > As > Ti > Be > V > U > C d > T l > Mo > Hg. The study revealed that the concentration of trace and toxic elements like Al, Cu, and Pb exceeded their corresponding WHO permissible standards. Hazard index (HI) values and total likely cancer risk (TLCR) values for non-carcinogenic and carcinogenic health risks indicate that 91.3% of the total sampling sites presented health concerns to adults and children. The mean TLCR values associated with exposure to carcinogenic metals via ingestion of groundwater samples were estimated to be 2.09 × 10-4 and 4.44 × 10-4 for adults and children respectively. Exposure through the ingestion pathway was found to be more risky compared to dermal contacts. Children are particularly vulnerable to these health hazards. Pearson correlation (PC) matrix, principal component analysis (PCA), and hierarchical cluster analysis (HCA) suggested that sources of TEs in the groundwater are attributed to both anthropogenic and geogenic factors.

Investigation of Lead, Cadmium, and Nickel in Water Samples from Al-Muthanna Governorate, Iraq, and Evaluation of The Pollution Indicators

Background: The Iraqi environment, especially in the southern region, has been contaminated as a result of human activities. The detection of heavy metals in water samples is the preferred method for monitoring the toxic levels, which are very important for environmental protection and human health. Methods: Heavy metal concentrations of lead (Pb), cadmium (Cd), and nickel (Ni) were investigated in water samples from Al-Muthanna governorate, southern Iraq. The selected water samples were taken from different sources of tap water and river samples from the Euphrates and collected from various locations: residential, agricultural, and industrial. Results: The mean values of Pb, Cd, and Ni in tap water samples are 3.76, 2.62, and 84.88 μg/L, respectively, while the corresponding element levels in river water are 11.21, 7.58, and 104.31 μg/L, respectively. Rivers water samples recorded higher levels of toxic metals than tap water samples. Concentrations of toxic elements in water samples from industrial locations of Al-Muthanna governorate are higher than in the agricultural and residential places. Toxic metals in water samples can be arranged in the following sequence: Ni &gt; Pb &gt; Cd. Conclusion: The levels of heavy metals in most water samples were above the permissible levels according to USEPA; therefore, it is recommended that the water samples should be regularly monitored for heavy metals to prevent the effect of heavy metals contamination in the human food chain.

Assessment of potentially toxic element contents in chickens and poultry feeds from Bangladesh markets: Implications for human health risk

Chicken (Gallus domesticus) is a significant source of animal protein for the people of Bangladesh. However, anthropogenic activity may contaminate chicken meat with potentially toxic elements (PTEs) despite the nutritional benefits. Current work aims to determine the accumulated content of PTEs (Pb, Cd, Cr, As, and Hg) in chickens and poultry feeds commercially sold in Bangladesh markets and compare with WHO, FAO, EU, EC, FSANZ standards. Three different chicken varieties, native (local variety, freehand raised), poultry (raised for meat only), and layer chicken (commercially raised for eggs and later used for meat), were investigated, and commercial poultry feeds were used to raise the latter two varieties. The Pb, Cd, Cr, As, and Hg contents (mg kg–1 fresh weight (f.w.) were 0.481–1.067, 0.025–0.118, 0.069–0.319, 0.007–0.071, 0.002–0.019, respectively. In addition, associated health risks due to the PTEs in different varieties of chicken organs, e.g., meat, liver, and kidney, were evaluated. The study suggests that the poultry feeds should be carefully monitored regarding PTEs content to avoid potential human health risks due to chicken consumption in Bangladesh.

Levels of potentially toxic and essential elements in Tocantins River sediment: health risks at Brazil’s Savanna-Amazon interface

The field study aims to address identified research gaps by providing valuable information on the concentration, spatial distribution, pollution levels, and source apportionment of toxic and essential elements in sediment samples from four sampling sites (P1: Beira Rio (urban area), P2: Bananal (rural area), P3: Embiral (rural area), P4: Cidelândia (rural area) distributed along the middle Tocantins River, Brazil. Samples were collected in 2023 from river sections and analyzed using various contamination índices (geoaccumulation index, contamination factor, enrichment factor, pollution load index, sediment pollution index, potential ecological risk coefficients, and integrated risk index). Results indicated that the levels of aluminum, iron, manganese, and selenium exceeded legal standards in that year. Chromium, nickel, copper, zinc, and lead exceeded guidelines, mainly in section P1 for aluminum and section P3 for nickel and lead. Rainy months showed increased presence, indicating seasonal variability. The geoaccumulation index indicated low pollution levels, with lead and nickel notably present near urban and industrial areas. The enrichment factor highlighted elevated concentrations of lead and zinc in industrial areas. Both PLI and SPI indices raise concerns regarding Pb (P4) and Zn (P3) concentrations at specific times of the year. Overall, potential ecological risks were deemed low for most sites. Continuous monitoring and interventions are crucial to preserve water and environmental quality in the region.

Statistical and geospatial assessment of trace and toxic elements distribution in ground and surface water of northern parts of the Indo-Gangetic plains: Source identification and health risk assessment

This study focusses on ground and surface water resources in the northern parts of the Indo-Gangetic Plains. The study aims to identify potential contaminants, analyse their distribution, trace their origins, and evaluate associated health risk. Samples from 80 locations; groundwater (n = 69) and surface water (n = 11) were analysed for nineteen trace and toxic elements using ICP-MS. Eight elements in groundwater (Mn, Fe, Ni, Zn, As, Tl, U and Se) and six in surface water (Al, Mn, Fe, Ni, Zn, and Tl) exceeded WHO (2011) and BIS (2012) limits in certain areas. The geospatial analysis reveals hotspots of trace and toxic element concentration, with higher levels detected in the southeast and western regions of the study area. Correlation matrices revealed a robust correlation (∼>0.75–0.99, p < 0.01) among all trace and toxic elements (excluding Li, Be, As, Ag, and U) in surface water samples when compared to groundwater samples. Cluster analysis and principal component analysis (PCA) (explains 70.09 cumulative percent for total 6 of factors) of groundwater chemistry indicates that Zn, Ni and Tl contamination may originate from industrial activities (metallurgical processes and manufacturing). The potential sources of Mn may be both geological and human-induced, while Fe, Se, As and U can originate from specific geological formations or human-related activities like over-extraction and leaching of excess fertilizers into aquifers. For surface water, PCA (explains 92.92 cumulative percent for total 5 of factors) identifies industrial activities as the main source of Mn, Fe, Tl, Ni, and Zn, while Al originates from both geological and anthropogenic sources. The water quality index indicated poor to very poor water quality in the western and central regions, whereas the northern and eastern regions exhibited excellent water quality. Health risk assessment reveals HI values for groundwater water: 3.85 (adults), 7.70 (children); surface water: 1.52 (adults), 3.05 (children), emphasizing the urgent need for remediation measures.

Bioaccumulation of metals in muscle tissues of economically important fish species from black sea Lagoon lakes in Türkiye: Consumer health risk and nutritional value assessment

This study is the first comprehensive investigation into the levels of potentially toxic elements (PTEs) in the muscle tissues of various fish species (Carassius gibelio, Squalis cephalus, Esox lucius, and Tinca tinca) in Lagoon Lakes Akgöl and Semenit (LLAS), Samsun, Türkiye. A multidisciplinary approach was employed, integrating elemental analysis, health risk assessment, and source identification techniques to evaluate the distribution, sources, and health risks of PTE contamination in fish. The mean concentrations of toxic and trace elements (µg/kg) were determined in ascending order: Cd (5) < Co (8) < Cr (18) = Pb (18) < Ni (66) < As (163) < Cu (290) < Mn (798) < Fe (6150) < Zn (6250). In contrast, the concentrations of macro elements are provided in units of mg/kg, as follows: Mg (391) < Na (677) < Ca (1698) < P (2314) < K (3837), with notable variations across species. Health risk assessment methodologies indicated that PTE levels in fish muscle tissues generally fell below regulatory limits, indicating their safety for consumption. Noncarcinogenic risk assessment further documented the safety of consuming these fish species, with elevated maximum safe consumption quantity (MSCQ) values observed for all metals. In addition, the estimated daily intake of PTEs was found to be below reference doses, confirming the safety of consumption. Esox lucius demonstrated a highest abundance of essential nutrients (e.g., Ca, K, Mg, and P). Source identification techniques indicated that residential waste, lithogenic materials, and agricultural practices are significant contributors to PTE contamination. Overall, this research stresses the importance of monitoring PTE levels in fish, ensuring food safety and protect human health.

Cumulative characteristics and ecological risk source analysis of soil potentially toxic elements in the northern margin of the Tibetan Plateau.

To understand the soil toxic and hazardous elements content, pollution level, and ecological risk status in the northern margin of the Tibetan Plateau, we collected and analyzed 8273 sets of surface soil samples. Evaluations were conducted using the single-factor pollution index, geo-accumulation, pollution load, and potential ecological risk indices, and source identification correlation and principal component analysis. The results revealed that, compared with the background levels in China, the accumulation of soil arsenic, cadmium, nickel, and chromium was greater in the surface soil of the study area. Additionally, in comparison with Qinghai Province, more mercury accumulated in the surface soil of the study area and owing to the influence of anthropogenic activities. Benchmarking against soil environmental quality standards, the study area exhibited pollution control zones primarily dominated by arsenic and cadmium (3.9%). The spatial distribution revealed distinct zones: a ridge mountain type characterized by arsenic-cadmium-chromium-nickel, a Daban mountain type with solely cadmium presence, and a Longyangxia-Jianzha South type dominated by arsenic. Compared with the Qinghai Province soil background values, evaluations using the Pollution loading index, Geological Cumulative Index, and Potential Ecological Risk Index methods revealed varying degrees of potentially toxic element content exceedance. From an ecological risk perspective, the individual element with the highest potential ecological risk coefficients were mercury, followed by cadmium and arsenic; however, the region's overall ecological risk index was classified as low. Three distinct sources were identified: natural sources leading to high background levels of chromium, nickel, copper, zinc, and mercury; mixed natural and industrial/agricultural sources contributing to elevated cadmium levels; and human activity-related mercury enrichment. Based on the evaluation results, synergistic monitoring of soil and biota in naturally occurring risk zones is recommended to ensure the safety of agricultural and pastoral products. Additionally, ecological impact assessments and pollution source mitigation studies should be conducted in regions influenced by human activities to curb the further degradation of soil ecological quality.

Assessment of water supply to the east European arctic agglomeration from groundwater, taking into account their quality and health risks

The purpose of the study is to assess the possibilities of using groundwater for water supply in the East European Arctic agglomeration based on an assessment of their quality and health risks. For this purpose, high-precision determinations of the complete macro- and microcomponent composition were carried out in sixty-six water samples taken from wells up to 180 m deep. It was found that in some samples the concentrations of Na+, Fe, B, Ba, Mn and U exceeded WHO standards. The least mineralized young waters are characterized by the processes of dissolution of carbonates with the transition of Ca, Mg, Ba, Sr into water, and the processes of leaching of Fe and Mn by acidic swamp waters from near-surface sediments. Waters of high mineralization, enriched in Na+, Cl-, B, Mo, Cd, Pb, were formed as a result of the dissolution of aluminosilicate rocks over thousands of years and mixing with relics of ancient and modern marine transgressions. An assessment of the average Water Quality Index value of the studied aquifer showed that, in general, the water is of excellent quality. Non-carcinogenic risks were determined primarily by uranium concentrations. The average danger index values for this element for children were 1.22. In adults it was slightly lower and amounted to 0.83. Carcinogenic risks are associated primarily with arsenic concentrations. The average total carcinogenic risk associated with this element was 3.8.10−5, which is acceptable, but samples from two wells showed total carcinogenic risk values above 10−4, which is in the high-risk area. For drinking purposes, it is preferable to use low-mineralized water with a minimum content of toxic elements. If necessary, preliminary aeration of the water is possible, during which precipitation of iron, arsenic and uranium occurs. Due to the typical nature of the problem under consideration for the Arctic regions, the results obtained can be used at other sites in the Subpolar zone.