Arsenic Values Research Articles

Driving mechanism of groundwater quality and probabilistic health risk quantification in the central Yinchuan Plain

The environmental changes from climatic, terrestrial and anthropogenic drivers can significantly influence the groundwater quality that may pose a threat to human health. However, the driving mechanism of groundwater quality and potential health risk still remains to be studied. In this paper, 165 groundwater samples were analyzed to evaluate the groundwater quality, driving mechanism, and probabilistic health risk in the central Yinchuan Plain by applying fuzzy comprehensive evaluation method (FCEM), redundance analysis (RDA) and Monte Carlo simulation. The results showed that hydrochemical evolution of groundwater were strongly influenced by water-rock interaction, evaporation and human activities. While 55.2% of groundwater samples reached the drinking water quality standard (Class I, II and III), 44.8% of samples exceeded the standard limits of Class III water quality (Class IV and V), indicating a high pollution level of groundwater. Mn, TDS, NH4+, NO3−, Fe, F−, NO2−, As were among major indicators that influence the groundwater quality due to the natural and anthropogenic processes. The RDA analysis revealed that climatic factors (PE: 10.9%, PRE: 1.1%), GE chemical properties (ORP: 20.7%, DO: 2.4%), hydrogeological factors (BD: 16.5%, K: 4.1%), and terrestrial factors (elevation: 1.2%; distanced: 5.6%, distancerl: 1.5%, NDVI: 1.2%) were identified as major driving factors influencing the groundwater quality in the study area. The HHRA suggested that TCR values of arsenic in infants, children and teens greatly exceeded the acceptable risk threshold of 1E-4, indicating a high cancer risk with a basic trend: infants > children > teens, while TCR values of adults were within the acceptable risk level. THI values of four age groups in the RME scenario were nearly ten times higher than those in the CTE scenario, displaying a great health effect on all age groups (HQ > 1). The present study provides novel insights into the driving mechanism of groundwater quality and potential health hazard in arid and semi-arid regions.

Heavy metals in wastewater and fish collected from waste stabilization pond and human health risks in southwestern Ethiopia

IntroductionThis study aimed to measure the concentration of toxic heavy metals in wastewater samples and Nile tilapia (Oreochromis niloticus) species inhabiting wastewater (waste stabilization ponds) and evaluate their safety as a food source in southwestern Ethiopia. For this purpose, toxic metals like lead (Pb), cadmium (Cd), arsenic (As), and mercury (Hg) in wastewater samples and fish tissues (muscle, gill, and liver) were independently examined.MethodsA laboratory-based cross-sectional study was performed to ascertain the levels of Pb, Cd, As, and Hg in the fish tissues of O. niloticus and wastewater samples. Heavy metal levels were analyzed by microplasma atomic emission spectrometry (Agilent 4210 MP-AES) and hydrogen-generated atomic absorption spectrometry (HGAAS, novAA 400P, Germany).ResultsHeavy metal concentrations were measured in the following decreasing order (µg L−1): Cd > Pb > As > Hg in facultative and maturation ponds, with Cd (27.66 µg L−1) having the highest concentration and Hg (0.349 µg L−1) having the lowest concentration. Among the heavy metals detected in the wastewater samples, Hg showed a statistically significant difference between the sampling points (p = 0.023). The maximum metal concentration was measured for Pb (0.35 mg kg−1) and Cd (0.24 mg kg−1) in the muscle tissue of O. niloticus. The value of arsenic (0.02 mg kg−1) detected in fish edible muscles exceeded the FAO/WHO maximum permissible limit (MPL = 0.01) for human consumption. The carcinogenic and non-carcinogenic health risks of consuming fish due to trace metals were relatively low and posed fewer potential threats to human health. According to this finding, children were more susceptible to heavy metal exposure than adults.ConclusionDue to the high quantities of these harmful heavy metals, wastewater from oxidation ponds should not be used for fishing to avoid bioaccumulation. The target carcinogenic risk (TR) and target hazard quotient (THQ) indicated that all heavy metals were below the safe threshold. This research will provide a baseline for monitoring trace metals in various edible aquatic creatures and for future research in artificial habitats and regulatory considerations.

Analysis of arsenic in rice and domestic water supply in Baguio City, Philippines

Numerous studies have found that rice and water, as components of the human diet, are potential pathways of arsenic exposure in humans. Due to the negative health effects linked with arsenic exposure, the quality of drinking water and rice samples must be continually monitored. This research was carried out in Baguio City, a small urban center in the Philippines. Following microwave digestion, arsenic in rice and water samples were determined using Atomic Absorption Spectrometry. The results showed that the National Food Authority (NFA) rice samples had arsenic content below the detection limit, indicating that this commercially available rice does not pose any health risk to Filipino consumers in terms of arsenic exposure. The arsenic value in other rice samples ranged from 8 μg/L to 27 μg/L, with the lowest and highest values found in organic brown rice and white rice varieties, respectively. Despite detectable arsenic in all 20 rice samples, all values were less than the maximum contaminant level (MCL) of 150 μg/L. Despite higher arsenic content in mixed rice than in white and organic colored rice, the mean differences are not significant, as proven by the Kruskal Wallis Test. All drinking water samples bought from water refilling stations had no detectable arsenic, while eight of the 18 (44%) of the spring water samples showed detectable amounts but are far below MCL of arsenic in drinking water. The findings suggest that the amount of arsenic in rice and spring water samples are too low to pose health risks over a short period of time.

Evaluation and health risk assessment of arsenic and potentially toxic elements pollution in groundwater of Majha Belt, Punjab, India.

Concentrations of potentially toxic elements (PTEs) like arsenic, uranium, iron, and nitrate in the groundwater of the Majha Belt (including Tarn Taran, Amritsar, Gurdaspur, and Pathankot districts) in Punjab, India were measured to evaluate the health risks associated with its consumption and daily use. The average concentrations of these elements in some locations exceeded the WHO-recommended values. Arsenic and iron toxicity levels were found to be higher in the Amritsar district, while uranium toxicity was more prevalent in Tarn Taran. The Trace Element Evaluation Index suggests that Amritsar is one of the districts most affected by toxic elements. According to the US Environmental Protection Agency's (USEPA) guidelines, the HQ values of U, Fe, and nitrate were less than one, indicating that there is no non-carcinogenic health risk for adults and children. However, the hazard quotient (HQ) value for arsenic was greater than one, indicating a higher possibility of health risk due to arsenic in the study area. The total hazard index values of 44.10% of samples were greater than four for arsenic, indicating that people in the Majha Belt are at a very high health risk due to the usage of water for drinking and domestic purposes. The cancer risk assessment values for arsenic in children (5.69E + 0) and adults (4.07E + 0) were higher than the accepted limit of USEPA (10-4 to 10-6) in the Majha Belt. The average radiological cancer risk values of U for children and adults were 8.68E-07 and 9.45E-06, respectively, which are well below the permissible limit of 1.67 × 10-4 suggested by the Atomic Energy Regulatory Board of DAE, India. The results of this study confirm that the residents of the Majha Belt who use contaminated groundwater are at a serious risk of exposure to arsenic in the Amritsar district and uranium in Tarn Taran district.

The analytical assessment of metal contamination in industrial soils of Saudi Arabia using the inductively coupled plasma technology

Abstract In response to significant demand for evaluating the presence of heavy elements in diverse industrial areas of Saudi Arabia, the study sought to analyze the concentration ratios of 16 elements across 11 different artificial soil types in the industrial zones situated in Riyadh, Sudair, and Al-Ahsa. To achieve this objective, the research utilized the wet digestion technique and employed an ICPE-9000 spectrophotometer for quantifying element concentrations. The study had a dual focus: initially, it sought to gauge the pollution attributed to heavy metals arising from enrichment processes, and second, it evaluated the geographical accumulation of pollutants in the soil. The results revealed varying concentration levels of heavy metals across the industrial areas under study. Specifically, the soil in the Yanbu region exhibited the highest concentration values for iron, manganese, zinc, chromium, nickel, copper, cobalt, cadmium, and beryllium. In contrast, the soil in the industrial area of Riyadh had the highest concentration values for lead, mercury (Hg), molybdenum (Mo), selenium (Se), and arsenic (As). Furthermore, the highest concentration of Cd was recorded in the soil of the Jubail region. Conversely, the soil in the Al-Ahsa region displayed the lowest concentration levels for these heavy metals. The conductivity of the synthetic soil ranged from 0.47 to 6.07 μS·cm−1, accompanied by a pH range of 6.6–8.6. The results emphasized the fluctuations in element concentrations, indicating significant implications for both environmental and human health. Notably, around 20% of the gathered samples showed concentrations of heavy elements like Mo, As, Hg, and Se that surpassed the allowable limits.

Arsenic contamination of groundwater: Review on arsenic contamination of Assam

Groundwater contamination is a global problem. Although groundwater is considered as safe, high concentrations of heavy metals in groundwater like arsenic (As) can pose potential human health concerns and hazards. Arsenic is a natural chemical element of the earth’s crust and is commonly distributed all over the environment. High concentrations of arsenic (As) in drinking water have been found in several parts of the world. World Health Organization’s provisional guideline value for arsenic in drinking water - 0.01 mg/l (10 μg/l). In Assam, many districts have been reported to be most affected by arsenic contamination of groundwater which is above the permissible level. People in Assam have directly or indirectly consumed the groundwater. This paper emphasizes the overview of the present scenario of intensity of arsenic contamination in groundwater in different districts of Assam. The paper also critically reviews the sources of arsenic contamination and arsenic led human effects.

The levels of mercury (Hg) and arsenic (As) in wild boar’s liver (Sus scrofa) in eleven hunting areas from the Republic of North Macedonia

The monitors have recently been defined as the organisms in which changes in known characteristics can be measured to assess the extent of the environmental contamination. Among the numerous game species, the wild boar as omnivore is characterized as an exceptionally good biomonitor. The concentrations of one heavy metal (Hg) and one metalloid (As) were measured using cold vapor atomic absorption spectrometer and atomic absorption spectrophotometry in the liver tissue of free-living wild boars. From 11 hunting areas locations that cover the whole territory of North Macedonia in a period of 7 years (2016-2022) a total of 608 wild boar liver samples were harvested during the regular hunting season. The mean concentration of Hg from 11 hunting grounds ranged from 12.7 μg/kg to 68.8 μg/kg, and mean concentration for all was 45.67 μg/kg. The average concentration of As ranged from 22 μg/kg to 55.3 μg/kg, and mean concentration for all was 33.1 μg/kg. For mercury, 6.56% or 40 of the total number of samples (608) exceeded the maximum allowed limits, and for arsenic none of the examined samples exceeded the allowed limit. For both elements a statistically significant difference was determined in relation to the years, with irregular oscillations from year to year. The mean values for mercury and arsenic are encouraging and generally indicate the relatively low contamination in the territory of the Republic of North Macedonia. However, the statistical differences due to the year as a factor suggest there is the need for the further research.

The Potential Use of Pseudomonas stutzeri as a Biocatalyst for the Removal of Heavy Metals and the Generation of Bioelectricity

Currently, industry in all its forms is vital for the human population because it provides the services and goods necessary to live. However, this process also pollutes soils and rivers. This research provides an environmentally friendly solution for the generation of electrical energy and the bioremediation of heavy metals such as arsenic, iron, and copper present in river waters used to irrigate farmers’ crops. This research used single-chamber microbial fuel cells with activated carbon and zinc electrodes as anodes and cathodes, respectively, and farmers’ irrigation water contaminated with mining waste as substrate. Pseudomonas stutzeri was used as a biocatalyst due to its ability to proliferate at temperatures between 4 and 44 °C—at which the waters that feed irrigated rivers pass on their way to the sea—managing to generate peaks of electric current and voltage of 4.35 mA and 0.91 V on the sixth day, which operated with an electrical conductivity of 222 mS/cm and a pH of 6.74. Likewise, the parameters of nitrogen, total organic carbon, carbon lost on the ignition, dissolved organic carbon, and chemical oxygen demand were reduced by 51.19%, 79.92%, 64.95%, 79.89%, 79.93%, and 86.46%. At the same time, iron, copper, and arsenic values decreased by 84.625, 14.533, and 90.831%, respectively. The internal resistance values shown were 26.355 ± 4.528 Ω with a power density of 422.054 mW/cm2 with a current density of 5.766 A/cm2. This research gives society, governments, and private companies an economical and easily scalable prototype capable of simultaneously generating electrical energy and removing heavy metals.

Dietary exposure and risk characterization of selected toxic metals in crude palm oil (Elaeis guineensis Jacq) from six states in Niger Delta, Nigeria

The increase in toxic metal (TM) contamination in crude palm oil (CPO) due to anthropogenic activities, method of processing and handling makes it necessary to assess the contents of metals of toxicological interest to ensure safety. The contents of TMs [lead (Pb), cadmium (Cd), chromium (Cr), nickel (Ni) and arsenic (As)] were quantified in CPO samples locally produced from six selected states in Niger Delta, Nigeria using atomic absorption spectrophotometer. The TM contents and dietary intakes were compared with permitted limits of international agencies such as the European Food Safety Authority (EFSA) and Joint FAO/WHO Expert Committee on Food Additives (JECFA). The TM contents exceeded the permissible limits of JECFA with Cr in Akwa Ibom State samples (3.08 mg kg-1) being the highest. The dietary monthly intake of Cd for consumption of 25 g day-1 of CPO for adults and children were 40.36 µg kg-bw-1 month-1 (161%) and 91.6 µg kg-bw-1 month-1 (366%), respectively. The margin of exposure (MOE) values of Pb due to consumption of CPO ranged from 1.39 to 3.83 (nephrotoxic effects) and 3.32 to 9.12 (cardiotoxic effects) for adults, and 0.49 to 1.34 (neurotoxic effect), 0.61 to 1.69 (nephrotoxic effects) and 0.61 to 4.01 (cardiotoxic effects) for children. Furthermore, MOE values of inorganic arsenic (iAs) for carcinogenic effects due to consumption of CPO for adults and children ranged from 0.32 to 26.53 and 0.14 to 11.69, respectively. The results highlight the necessity to set up monitoring program for TMs in CPO to reduce exposure level.

Dynamics of Spatiotemporal Variation of Groundwater Arsenic in Central Rift Vally of Ethiopia: A Serial Cross-Sectional Study.

Arsenic is a well-known, highly poisonous metalloid that affects human health and ecosystems and is widely distributed in the environment. Nevertheless, data on the spatiotemporal distribution of arsenic in groundwater sources in Ethiopia are scarce. The principal aim of this study was to assess the extent of arsenic in groundwater sources and analyze the spatiotemporal variations in the central rift valley of Ethiopia. The study employed a serial cross-sectional study design and census sampling methods. The concentrations of arsenic in the groundwater samples were determined using inductively coupled plasma mass spectrometry (ICP-MS) at the Ethiopian Food and Drug Authority laboratory. Descriptive statistical analyses were performed using IBM SPSS version 29 software. Additionally, ArcGIS software was utilized to map the spatiotemporal distribution of arsenic. Furthermore, Minitab statistical software version 21.4 was employed to assess the correlation between spatiotemporal variations of arsenic concentrations in groundwater sources. The mean values of arsenic in the groundwater samples were 11.2 µg/L during the dry season and 10.7 µg/L during the rainy season. The study results showed that 18 wells (42.2%) and 22 wells (48.8%) had higher arsenic concentrations (>10 µg/L) during the dry and rainy seasons, respectively. Thus, arsenic levels in 42.2% and 48.8% of the samples exceeded the maximum threshold limit set by WHO, USEPA, and Ethiopian standards (10 µg/L), respectively, during the dry and rainy seasons. Furthermore, our analysis revealed a significant positive correlation between arsenic in groundwater and well depth (r = .75, P < .001), indicating a strong association between higher arsenic concentrations and deeper wells. Similarly, we observed a substantial positive correlation between arsenic concentration in groundwater and season (r = .9, P < .001), suggesting notable variations in arsenic levels between dry and rainy seasons. The majority of the groundwater sources in the studied area are unfit for human consumption because they contain high amounts of arsenic, which poses a significant risk to human health. Moreover, the arsenic concentration varied spatially and temporally. Therefore, special attention is needed to reduce arsenic exposure and associated health risks.

Assessment of the status of selected heavy metals in water, sediments and a fish species (Oreochromis niloticus) of commercial value in Lake Nakuru with a focus on human health risks

AbstractThe present study presents selected water quality parameters and the levels of heavy metals in water, sediments and Nile tilapia (Oreochromis niloticus) of Lake Nakuru. Nine sediments and nine water samples, as well as 30 specimens of Nile tilapia, were collected from the northern part of the lake. Physical parameters were measured in situ using multiple probes and metres. Heavy metals were analysed using an atomic absorption spectrophotometer (AAS). The pH, dissolved oxygen concentration, temperature, salinity and electrical conductivity ranged from 9.52 to 9.72, 4.58 to 8.62 mg/L, 23.40°C to 25.7°C, 2.39‰ to 2.81‰ and 4470–5226 μs/cm, respectively. Heavy metal levels (mean ± SD) were generally low in the water samples. Chromium values ranged between 7.16 and 9.19 mg/kg dw in sediment samples, and between 3.7 and 13.06 mg/kg dw in fish samples. Lead values ranged between 12.5 and 31.04 mg/kg dw in sediment samples and 4.06 and 9.95 mg/kg dw in fish samples. Arsenic values ranged between 9.5 and 21.7 mg/kg dw in sediments and below detectable limit to 2.11 mg/kg dw in fish samples. Mercury values ranged between .14 and .31 mg/kg dw in sediment samples and .12 and .35 mg/kg dw in fish samples. Cadmium was the only heavy metal concentration that was below the detection limit in the three matrices. Significant differences were observed for some heavy metal concentrations in water, sediments and fish across sites (p &lt; .05). The levels of lead and chromium in fish were above the East African Standard, World Health Organization and European Union limits. The results of the present study recommend a possible reclassification of the lake, an immediate ban on fish harvesting and consumption from Lake Nakuru and a policy intervention on the fishery and pollution management.

Association between Heavy Metal Exposure and Idiopathic Aplastic Anemia in Adolescents and Adults:a Case Control Study from Northern India

Introduction:Compared to western world the incidence of AA in South Asian countries is higher. There are studies to suggest that incidence of this disease is 2-3 times higher in LMICs. Besides immune mediated pathophysiology and inherited presdispostion, toxic insult to the hematopoietic elements due to chemotherapy, radiation exposure, drugs,and environmental toxins such as pesticides and heavy metals have been associated with Aplastic Anemia.The higher incidence of AA in lower socio-economic status and its association with drinking water habits, industrial exposure suggests a possible link with heavy metals in the pathogenesis of disease. Methodology:Fifty patients diagnosed with idiopathic aplastic anaemia and 50 age and gender matched healthy controls were included in the study. 2 ml of blood and 20 hair shafts were collected as samples from each subject for the analysis of arsenic, lead, cadmium, mercury, and thallium in both samples by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Results:The total study population consisted of 61 males and 39 females. 42% of the cases were residents of rural areas, and 58% belonged to urban areas. 54% participants among the controls belonged to rural areas. Among the total population, 48% cases and 58% controls were using tap water as major source of water. Out of the total participant in the study, 10% of the cases and 12% of the controls were found to be exposed to pesticides previously, however no direct occupational exposure of heavy metal was found among the study population. Twenty-three patients (46%) had NSAA, and 15 patients had SAA (30%) while 12 patients (24%) had VSAA.Mean values of arsenic in blood of patients and controls are 3.52±2.9mcg/L,and 0.0mcg/L respectively and the difference was statistically significant (p &amp;lt;0.001) however the mean arsenic values in hair of cases and controls were not different significantly(0.13±0.1mg/g and 0.15±0.1mg/g;p=0.16).Mean values of cadmium in blood of patients and controls were 2.5±1.9mcg/L and 0 mcg/L (p &amp;lt;0.001). Mean values of cadmium in hair of patients and controls are 0.10±0.16, 0.13±0.28 respectively.We noticed blood cadmium higher than safer limits in 24% of cases none in the controls.We found 6% of cases had higher than permissible limit of mercury level and 8% of cases have higher than permissible limit of lead level in their hair samples which represent chronic exposure. Conclusion: We found higher mean values of blood Arsenic and blood Cadmium in cases compared to controls. Upto one fourth cases had higher than safety levels of cadmium in their blood. Although causal association cannot be determined in this study our results indicate that heavy metal toxicity may be one of the reasons for AA in regions with higher environmental exposure and soil and water contamination.

Utilizing machine learning algorithm for finely three-dimensional delineation of soil-groundwater contamination in a typical industrial park, North China: Importance of multisource auxiliary data

Intensive industrial activities cause soil contamination with wide variations and even perturb groundwater safety. Precision delineation of soil contamination is the foundation and precondition for soil quality assurance in the practical environmental management process. However, spatial non-stationarity phenomenon of soil contamination and heterogeneous sampling are two key issues that affect the accuracy of contamination delineation model. Taking a typical industrial park in North China as the research object, we constructed a random forest (RF) model for finely characterizing the distribution of soil contaminants using sparse-biased drilling data. Results showed that the R2 values of arsenic and 1,2-dichloroethane predicted by RF (0.8896 and 0.8973) were greatly higher than those of inverse distance weighted model (0.2848 and 0.2908), indicating that RF was more adaptable to actual non-stationarity sites. The back propagation neural network algorithm was utilized to establish a three-dimensional visualization of the contamination parcel of subsoil-groundwater system. Multiple sources of environmental data, including hydrogeological conditions, geochemical characteristics and anthropogenic industrial activities were integrated into the model to optimize the prediction accuracy. The feature importance analysis revealed that soil particle size was dominant for the migration of arsenic, while the migration of 1,2-dichloroethane highly depended on vertical permeability coefficients of the soil. Contaminants migrated downwards with soil water under gravity-driven conditions and penetrated through the subsoil to reach the saturated aquifer, forming a contamination plume with groundwater flow. Our findings afford a new idea for spatial analysis of soil-groundwater contamination at industrial sites, which will provide valuable technical support for maintaining sustainable industry.

Investigating the impacts of heavy metal(loid)s on ecology and human health in the lower basin of Hungary’s Danube River: A Python and Monte Carlo simulation-based study

This study aimed to determine the environmental and health risks of the heavy metal levels in the Danube River in Hungary. The metals, including Fe, Mn, Zn, Cu, Ni, Cr, Pb, and As, were measured in the period from 2013 to 2019. The Spearman correlation and heatmap cluster analysis were utilized to determine the origin of pollution and the factors that control surface water quality. Several indices, such as the heavy metal pollution index (HPI), metal index (MI), hazard quotient oral and dermal (HQ), hazard index oral and dermal (HI), and carcinogenic risk (CR), were conducted to evaluate the potential risks for the environment and human health. The values of the HPI were between the range of 15 < HPI < 30, which indicated moderate pollution; however, the MI results showed high pollution in Dunaföldvár and Hercegszántó cities. The ecological risk (RI < 30) and HI values (< 1) showed low environmental risks and non-carcinogenic impacts of the existing metals, either on adults or children. The mean CR value of oral arsenic was 2.2E−04 and 2.5E−04 during April–September and October–March, respectively, indicating that children were the most vulnerable to arsenic-carcinogenic oral effects. While lead’s CR oral values for children during April–September exceeded the threshold of 1.0E−04, chromium’s oral and dermal CR values for both adults and children were 2.08E−04, 6.11E−04, 1.97E−04, and 5.82E−04 during April–September and October–March, respectively. These results demonstrate the potential carcinogenic risks related to chromium exposure within the two pathways in Hungary and highlight the need for effective measures to mitigate these risks.

Assessing the health risks of coal-burning arsenic-induced skin damage: A 22-year follow-up study in Guizhou, China

Risk assessment of arsenic-induced skin damage has always received significant global attention. Theories derived from arsenic exposure in drinking water may not be applicable to the coal-burning type to arsenic-exposed area. Furthermore, very few studies have successfully determined the reference value of cumulative arsenic (CA) exposure that leads to specific skin lesions. In this study, we conducted a 22-year follow-up investigation to assess the risk of skin lesions and cancer resulting from long-term, multi-channel arsenic exposure from hazard identification, dose-response assessment, exposure assessment, and risk characterization. The results show that the arsenic exposure can significantly increase the prevalence of skin lesions. For each interquartile range increase of hair arsenic (HA) and CA, the risk of skin damage increased by 1.91 and 3.90 times, respectively. The lower confidence limit of the benchmark dose of HA of arsenic-induced various skin lesions ranged from 0.07 to 0.12 μg·g−1, and 932.57 to 1368.92 mg for CA. The chronic daily intake, lifetime average daily dose in the arsenic-exposed area after the comprehensive prevention and control measures have decreased significantly, but remained higher than the daily baseline level of 3.0 μg·kg−1·d−1. Even as recently as 2020, the hazard quotients and hazard index still exceeded 1, measuring 155.33 and 55.20, and the lifetime excess risk of skin cancer (2.80 × 10−3) remains significantly higher than the acceptable level of 10−6. Our study underscores the effectiveness of comprehensive prevention and control measures in managing high arsenic exposure in coal-burning arsenic poisoning areas. However, it is crucial to acknowledge that the risk of both non-carcinogenic and carcinogenic effects on the skin remains substantially higher than the acceptable level. We recommend setting reference limits for monitoring skin damage among individuals exposed to arsenic, with a recommended upper limit of 0.07 μg·g−1 for HA and a maximum acceptable level of 935.57 mg for CA.

Association between arsenic (+3 oxidation state) methyltransferase gene polymorphisms and arsenic methylation capacity in rural residents of northern China: a cross-sectional study.

Arsenic is a toxic metal-like element. The toxic reaction of the body to arsenic is related to the ability of arsenic methylation metabolism. As the rate-limiting enzyme of arsenic methylation metabolism, the genetic single nucleotide polymorphisms (SNPs) of arsenic (+ 3 oxidation state) methyltransferase (AS3MT) gene are related to capacity of arsenic methylation. In this paper, we investigated the association of five SNPs (rs7085104, rs3740390, 3740393, rs10748835, and rs1046778) in AS3MT with arsenic methylation metabolizing using the data and samples from a cross-sectional case-control study of arsenic and Type 2 diabetes mellitus conducted in Shanxi, China. A total of 340 individuals were included in the study. Urinary total arsenic (tAs, μg/L) was detected by liquid chromatography-atomic fluorescence spectrometry (LC-AFS). According to "safety guidance value of urinary arsenic for population" as specified in WS/T665-2019 (China), participants were divided into the control group (tAs ≤ 32μg/L, n = 172) and arsenic-exposed group (tAs > 32μg/L, n = 168). iAs%, MMA%, and DMA% are as the indicator of arsenic methylation capacity. The genotypes of AS3MT SNPs were examined by Multiple PCR combined sequencing. Linear regression analysis showed that AG + GG genotype in rs7085104 was associated with decreased iAs% and increased DMA%. Moreover, AG + AA genotype in rs10748835 and TC + CC genotype in rs1046778 were associated with decreased iAs% and MMA% and increased DMA%. The interaction between rs7085104 and arsenic is associated with iAs% and DMA%. The interaction of rs3740390 and rs10748835 with arsenic is associated with iAs%. Haplotype CTAC (rs3740393-rs3740390-rs10748835-rs1046778) was associated with lower iAs% and higher DMA%, but this association disappeared after adjusting for age, gender, drink, smoking, BMI and tAs. Haplotype GCAC was associated with decreased MMA%. Our study provides additional support for revealing the factors influencing the metabolic capacity of arsenic methylation and might be helpful to identify the population susceptible to arsenic exposure through individualized screening in the future.

Arsenic source analysis of rice from different growing environments and health risk assessment in Hunan Province, China

Rice is an important pathway for arsenic dietary intake. Hunan Province is the major rice-producing region in China and is rich in mineral resources. To evaluate the sources of arsenic contamination in rice and health risks associated with rice consumption, the arsenic content in rice, paddy soils, and irrigation water in Hunan Province was analyzed. The results showed that the mean values of total arsenic (tAs) were 132 ± 42, 198 ± 95, 521 ± 390, and 2050 ± 3300 μg/kg in milled rice, brown rice, rice bran, and rice husk, respectively. Inorganic arsenic (iAs) was the dominant species in rice, accounting for 78.1% and 85.9% of tAs in milled rice and brown rice, respectively. Moreover, the contents of iAs in rice husk, bran, and brown rice were 19.7, 4.81, and 1.65 times higher than that in milled rice. Arsenic accumulation rice was mainly from irrigation water, and high tAs in soil may not necessarily cause increased concentrations in rice. Based on the target hazard quotient (THQ) and margin of exposure (MOE) values, residents will not encounter a significant noncarcinogenic risk (THQ < 1) through rice consumption; however, contaminated rice poses a potential carcinogenic risk in Hunan Province (MOE < 100).

Human biomonitoring of inorganic elements in a representative sample of the general population from Cape Verde: Results from the PERVEMAC-II study

Inorganic elements such as heavy metals and other potentially toxic elements are frequently detected in humans. The aim of the present study was to analyze the blood concentrations of 49 inorganic elements in a cohort of 401 subjects from Cape Verde. The study was performed in the frame of the Pesticide Residues in Vegetables of the Macaronesia project (PERVEMAC-II). Concentration of inorganic elements, including elements in the ATSDR's priority pollutant list and rare earth elements (RREs) were measured by ICP-MS in the whole blood of participants. A total of 20 out of 49 elements (40.8%) were detected in ≥20% of participants. Arsenic, copper, mercury, lead, selenium, strontium and zinc were detected in ≥99% of samples. Among the REEs, 7 showed detection frequencies above 20%. The median number of different elements detected was 15. In the present series, 77.0, 99.2 and 33.4% of the participants showed values of arsenic, mercury and lead higher than Reference Values 95%. These percentages were much higher than those reported in similar studies. Niobium and tantalum showed the highest median concentrations: 1.35 and 1.34 ng/mL, suggesting an environmental source of these valuable REEs in Cape Verde. Age appeared as the most important factor influencing the blood levels of inorganic elements. Lifestyle had an effect on the concentration of some of these elements. Those subjects whose water source was pond water had significantly higher arsenic levels. The concentration of ∑REEs was significantly higher among individuals who purchase their food in supermarkets (P = 0.013). These variables are of relevance since they can be controlled individually to reduce exposure to these contaminants. Our results may be useful for the implementation of public health measures by the competent authorities.

Biogenic Elements and Heavy Metals in Hermann's Tortoises-Testudo hermanni: Effect on Serum Biochemistry and Oxidative Status Parameters.

Conservation of species diversity is the need of the hour for preserving life forms on Earth. Extinction of any part of the ecosystem has negative impacts on many processes and systems. The objective of this work was to analyze some biochemical and molecular indicators and their correlations to biogenic elements and heavy metals in Testudo hermanni (n = 16). Biochemical parameters were analyzed using the commercial kit DiaSys and biochemical analyzer Randox RX Monza. Sodium, potassium, and chlorides were measured using the EasyLite analyzer. Oxidative stress was evaluated using colorimetric and luminometric methods. Quantification of chemical elements in the blood was carried out using inductively coupled plasma mass spectrometry (ICPS). Biochemical values of analyzed samples from Hermann's tortoises were almost the same as referential values described by multiple authors, with minor aberrations in the total protein parameter. Values of arsenic (As) and nickel (Ni) showed correlation with biochemical parameters and the parameters of oxidative stress. Cadmium (Cd) exhibited correlation with aspartate aminotransferase (AST). This study reports correlations among four heavy metals, and their levels were again correlated with biochemical and molecular parameters in Hermann's tortoises.

Arsenic level in drinking water, its correlation with water quality parameters, and associated health risks.

This study aimed to evaluate the occurrence and likelihood of health risks related to arsenic in drinking water of all counties of the Hamadan province in the northwest of Iran. In this work, 370 samples were collected from all of the water resources of urban and rural regions, during 5years (2017 to 2021). Oracle Crystal Ball software was used to perform the Monte Carlo simulation and investigate the potential health risks. According to the results, the average values of arsenic in the nine counties were in the order Kabudarahang (40.1ppb), Malayer (13.1ppb), Nahavand (6.1ppb), Bahar (2.05ppb), Famenin (0.41ppb), Asadabad (0.36ppb), Tuyserkan (0.28ppb), Razan (0.14ppb), and Hamadan (< 0.1ppb). The highest concentration of arsenic occurred in Kabudarahang with a maximum value of 185ppb. In the spring season, the average concentration of the cations, including calcium, magnesium, sodium, lead, cadmium, and chromium, obtained 109.51mg/l, 44.67mg/l, 20.50mg/l, 88.76ppb, 0.31ppb, and 0.02ppb, respectively. Based on the Delphi classification, the P 90% of oral lifetime cancer risk, in Hamadan province, were within level II (low risk) to VII (extremely high risk). The risk analysis revealed there was a possible carcinogenic risk to humans from oral exposure to As-contaminated groundwater, especially in Kabudarahang county. Therefore, there is an urgent need for management and precise measures in contaminated areas to reduce and prevent the adverse health effects of arsenic.