Levels Of Arsenic In Water Research Articles

Marine and terrestrial contributions to atmospheric deposition fluxes of methylated arsenic species

Arsenic, a toxic element from both anthropogenic and natural sources, reaches surface environments through atmospheric cycling and dry and wet deposition. Biomethylation volatilizes arsenic into the atmosphere and deposition cycles it back to the surface, affecting soil-plant systems. Chemical speciation of deposited arsenic is important for understanding further processing in soils and bioavailability. However, the range of atmospheric transport and source signature of arsenic species remain understudied. Here we report significant levels of methylated arsenic in precipitation, cloud water and aerosols collected under free tropospheric conditions at Pic du Midi Observatory (France) indicating long-range transport, which is crucial for atmospheric budgets. Through chemical analyses and moisture source diagnostics, we identify terrestrial and marine sources for distinct arsenic species. Estimated atmospheric deposition fluxes of methylated arsenic are similar to reported methylation rates in soils, highlighting atmospheric deposition as a significant, overlooked source of potentially bioavailable methylated arsenic species impacting plant uptake in soils.

Cancer incidence associations with drinking water arsenic levels and disinfection methods in Maine, USA

ABSTRACT Maine is a largely rural state where nearly half of the population uses drinking water from private wells. Arsenic (As) is present in some groundwater in the state and has been linked to cancer, and a lack of testing and treatment may expose people with private wells to elevated As levels. Disinfection byproducts (DBPs) include known and suspected carcinogens that form when chlorine or chloramines are added to water. People served by public water systems may be exposed to elevated levels of regulated DBPs such as trihalomethanes and haloacetic acids associated with chlorine and/or unregulated nitrogenous DBPs, or N-DBPs, such as nitrite and N-nitrosodimethylamine associated with chloramines. Contrary to initial expectations, there were no significant associations between median town As in well water and bladder, lung, kidney, or skin cancer incidence. Furthermore, bladder, melanoma, and other skin cancer incidence rates were negatively correlated with the percent of the town population using private wells. Analysis of cancer incidence associated with chlorine and chloramine disinfection showed elevated melanoma, and other skin cancer with chloramine use and elevated bladder and non-melanoma skin cancer with chlorine use compared to the no disinfectant case. We recommend more research on the links between disinfectant use and cancer.

Rapid and noninvasive estimation of human arsenic exposure based on 4-photo-set of the hand and foot photos through artificial intelligence

Chronic exposure to arsenic is linked to the development of cancers in the skin, lungs, and bladder. Arsenic exposure manifests as variegated pigmentation and characteristic pitted keratosis on the hands and feet, which often precede the onset of internal cancers. Traditionally, human arsenic exposure is estimated through arsenic levels in biological tissues; however, these methods are invasive and time-consuming. This study aims to develop a noninvasive approach to predict arsenic exposure using artificial intelligence (AI) to analyze photographs of hands and feet. By incorporating well water consumption data and arsenic concentration levels, we developed an AI algorithm trained on 9988 hand and foot photographs from 2497 subjects. This algorithm correlates visual features of palmoplantar hyperkeratosis with arsenic exposure levels. Four pictures per patient, capturing both ventral and dorsal aspects of hands and feet, were analyzed. The AI model utilized existing arsenic exposure data, including arsenic concentration (AC) and cumulative arsenic exposure (CAE), to make binary predictions of high and low arsenic exposure. The AI model achieved an optimal area under the curve (AUC) values of 0.813 for AC and 0.779 for CAE. Recall and precision metrics were 0.729 and 0.705 for CAE, and 0.750 and 0.763 for AC, respectively. While biomarkers have traditionally been used to assess arsenic exposure, efficient noninvasive methods are lacking. To our knowledge, this is the first study to leverage deep learning for noninvasive arsenic exposure assessment. Despite challenges with binary classification due to imbalanced and sparse data, this approach demonstrates the potential for noninvasive estimation of arsenic concentration. Future studies should focus on increasing data volume and categorizing arsenic concentration statistics to enhance model accuracy. This rapid estimation method could significantly contribute to epidemiological studies and aid physicians in diagnosis.

Impact of Droughts on Served Drinking Water Disparities in California, 2007-2020.

Objectives. To quantify the impact of droughts on drinking water arsenic and nitrate levels provided by community water systems (CWSs) in California and to assess whether this effect varies across sociodemographic subgroups. Methods. I integrated CWS characteristics, drought records, sociodemographic data, and regulatory drinking water samples (n = 83 317) from 2378 water systems serving 34.8 million residents from 2007 to 2020. I analyzed differential drought effects using fixed-effect regression analyses that cumulatively accounted for CWS-level trends, income, and agricultural measures. Results. CWSs serving majority Latino/a communities show persistently higher and more variable drinking water nitrate levels. Drought increased nitrate concentrations in majority Latino/a communities, with the effect doubling for CWSs with more than 75% Latino/a populations served. Arsenic concentrations in surface sources also increased during drought for all groups. Differential effects are driven by very small (< 500) and privately owned systems. Conclusions. Impending droughts driven by climate change may further increase drinking water disparities and arsenic threats. This underscores the critical need to address existing inequities in climate resilience planning and grant making. (Am J Public Health. 2024;114(9):935-945. https://doi.org/10.2105/AJPH.2024.307758).

Arsenic speciation analysis in human urine for long term epidemiological studies: The Multi-Ethnic Study of Atherosclerosis (MESA)

Arsenic is a ubiquitous toxic metalloid causing serious health problems. Speciation analysis of arsenic in human urine provides valuable insights for large-scale epidemiological studies and informs on sources of exposure as well as human metabolism. The Multi-Ethnic Study of Atherosclerosis (MESA) is a valuable cohort for assessing chronic low-moderate arsenic exposure and health effects in an ethnically diverse US population. We present a state-of-the-art arsenic speciation analysis methodology and its application to 7677 MESA spot urine samples based on high-performance liquid chromatography coupled to inductively coupled plasma mass spectrometry. This method is fast, robust and detects a total of 11 individual As species at method detection limits of 0.02–0.03 μg arsenic/L urine for each individual species. Our analytical approach features excellent mean method accuracy (98%) and precision (5%) for the main arsenic species in urine (arsenobetaine, methylarsonic acid, dimethylarsinic acid, and total inorganic As); intra- (3–6%) and inter-day coefficients of variability (5–6%); column recovery (96 ± 7%); and spike recovery (97 ± 6%). The main arsenic species were detectable in ≥95% of urine samples due to the implementation of an oxidation step. Each individual minor arsenic species was detectable in ≤25% of all urines, although at least one of them was detected in almost half the participants. We identified two minor urinary arsenic species as dimethylarsinoylacetic acid and dimethylarsinoylpropionic acid, potential metabolites of seafood-related arsenicals. We observed differences in individual As species excretion by race/ethnicity, with Asian-American participants featuring 3–4 times higher concentrations compared to other participants. We also found differences by site, body mass index, smoking status, rice intake, and water arsenic levels, potentially indicating different exposures or related to individual bio-metabolism. The proposed approach is suitable for epidemiological studies and the collected data will constitute the base for future research on potential health effects of chronic low-level arsenic exposure.

Association of Water Arsenic With Incident Diabetes in U.S. Adults: The Multi-Ethnic Study of Atherosclerosis and the Strong Heart Study.

We examined the association of arsenic in federally regulated community water systems (CWS) and unregulated private wells with type 2 diabetes (T2D) incidence in the Strong Heart Family Study (SHFS), a prospective study of American Indian communities, and the Multi-Ethnic Study of Atherosclerosis (MESA), a prospective study of racially and ethnically diverse urban U.S. communities. We evaluated 1,791 participants from SHFS and 5,777 participants from MESA who had water arsenic estimates available and were free of T2D at baseline (2001-2003 and 2000-2002, respectively). Participants were followed for incident T2D until 2010 (SHFS cohort) or 2019 (MESA cohort). We used Cox proportional hazards mixed-effects models to account for clustering by family and residential zip code, with adjustment for sex, baseline age, BMI, smoking status, and education. T2D incidence was 24.4 cases per 1,000 person-years (mean follow-up, 5.6 years) in SHFS and 11.2 per 1,000 person-years (mean follow-up, 14.0 years) in MESA. In a meta-analysis across the SHFS and MESA cohorts, the hazard ratio (95% CI) per doubling in CWS arsenic was 1.10 (1.02, 1.18). The corresponding hazard ratio was 1.09 (0.95, 1.26) in the SHFS group and 1.10 (1.01, 1.20) in the MESA group. The corresponding hazard ratio (95% CI) for arsenic in private wells and incident T2D in SHFS was 1.05 (0.95, 1.16). We observed statistical interaction and larger magnitude hazard ratios for participants with BMI <25 kg/m2 and female participants. Low to moderate water arsenic levels (<10 µg/L) were associated with T2D incidence in the SHFS and MESA cohorts.

Arsenic Exposure-Related Hypertension in Bangladesh and Reduced Circulating Nitric Oxide Bioavailability.

Hypertension is a major cause of death worldwide. Although arsenic exposure has been associated with the risk of hypertension, this association appears nonuniform due to inconsistent results from studies conducted in different populations. Moreover, hypertension is a complex condition with multiple underlying mechanisms and factors. One factor is impaired production and bioavailability of vascular nitric oxide (NO). However, the implications of the effects of arsenic exposure on circulating NO and its association with hypertension in humans are largely unknown. We investigated the dose-response relationship between arsenic exposure and hypertension with vascular NO levels as a potential mediator of arsenic-related hypertension in individuals exposed to a broad range of arsenic. A total of 828 participants were recruited from low- and high-arsenic exposure areas in Bangladesh. Participants' drinking water, hair, and nail arsenic concentrations were measured by inductively coupled plasma mass spectroscopy. Hypertension was defined as a systolic blood pressure (SBP) value of and a diastolic (DBP) value of . Serum NO levels reflected by total serum nitrite concentrations were measured by immunoassay. A formal causal mediation analysis was used to assess NO as a mediator of the association between arsenic level and hypertension. Increasing concentrations of arsenic measured in drinking water, hair, and nails were associated with the increasing levels of SBP and DBP. The odds of hypertension were dose-dependently increased by arsenic even in participants exposed to relatively low to moderate levels () of water arsenic [odds ratios (ORs) and 95% confidence intervals (CIs): 2.87 (95% CI: 1.28, 6.44), 2.67 (95% CI: 1.27, 5.60), and 5.04 (95% CI: 2.71, 9.35) for the , , and groups, respectively]. Causal mediation analysis showed a significant mediating effect of NO on arsenic-related SBP, DBP, and hypertension. Increasing exposure to arsenic was associated with increasing odds of hypertension. The association was mediated through the reduction of vascular NO bioavailability, suggesting that impaired NO bioavailability was a plausible underlying mechanism of arsenic-induced hypertension in this Bangladeshi population. https://doi.org/10.1289/EHP13018.

Chemical composition of arsenic-based acid mine drainage in the downstream of a gold mine: Fuzzy regression and clustering analysis

This study employs fuzzy regression and fuzzy multivariate clustering techniques to analyze arsenic-polluted water samples originating from acid rock drainage in waste rock dumps. The research focuses on understanding the complex relationships between variables associated with arsenic contamination, such as water arsenic concentration, pH levels, and soil characteristics. To this end, fuzzy regression models were developed to estimate the relationships between water arsenic concentration and independent variables, thus, incorporating the inherent uncertainties into the analysis. Furthermore, multivariate fuzzy k-means clustering analysis facilitated the identification of fuzzy-based clusters within the dataset, providing insights into spatial patterns and potential sources of arsenic pollution. The pairwise comparisons indicated the strongest correlation of 0.62 between soil total arsenic and pH, while the weakest correlation of 0.13 was observed between soil-soluble arsenic and soil iron, providing valuable insights into their relationships and impact on water arsenic levels. The associated uncertainties in the relationships among the variables were determined based on the degree of belongingness of each data point to various fuzzy sets. Three distinct clusters emerged from the analysis: Cluster 1 comprised Points 5, 6, and 7; Cluster 2 included Points 1, 2, 3, 4, 8, and 9; and Cluster 3 consisted of Points 10, 11, 12, and 13. The findings enhance our understanding of the factors influencing arsenic contamination to provide an effective mitigation strategy in acid rock drainage scenarios. This research also demonstrates the applicability and effectiveness of fuzzy regression and fuzzy multivariate clustering in the analysis of arsenic-polluted water samples.

Arsenic levels in rice brands sold in Kampala: an experimental study to show the modifying effect of boiling, soaking and washing

Arsenic is an important environmental pollutant with potential cancer-causing effects. It contributes to acute and chronic toxicity depending on the doses or duration of exposure. In this study, we estimated the concentration of total arsenic in different rice brands sold in Uganda, where rice is a staple food. We conducted an experimental study. Different rice brands were obtained from supermarkets and grocery shops, and assessed for arsenic using atomic absorption spectrometry. The concentrations of arsenic in rice were estimated after boiling, washing, or overnight soaking in plenty of water to see if these methods reduce arsenic levels efficiently in food. The concentrations of arsenic in the different rice brands were compared using an unpaired t-test after setting a p-value of ≤0.05 as significant. The G-rice brand had the lowest arsenic levels of 1.4±0.0002 ppm and the C-rice brand had the highest levels of 2.4±0.004 ppm. The tap water used to boil, soak and wash the rice brands had much higher arsenic levels of 3.5±0.000003 ppm, leading to increased retention of the heavy metal in the rice. Rice brands sold in Kampala city seem to have higher than acceptable arsenic levels. Increased vigilance in terms of routine monitoring for the levels of arsenic in rice and water used during food preparation by the Ugandan food or water safety regulatory authorities is highly recommended.

Optimizations towards a nearly invariable WO3-functionalized electrochemical aptasensor for ultra-trace identification of arsenic in lake water

Prolonged exposure to elevated levels of arsenic in water can lead to serious health problems and its efficient detection is vital for preventing acute arsenic poisoning incidents. The nanomaterial based electrochemical detection offers advantages in terms of high sensitivity, selectivity, and potential for compact, portable testing systems; albeit suffers from inter-device variability. This work presents a highly sensitive aptamer-based nano-biosensor for efficiently detecting arsenic in water through the electrochemical method using glassy carbon electrodes modified with tungsten trioxide (WO3) nanomaterial. The aptasensor in conjunction with electrochemical impedance spectroscopy (EIS) and differential pulse voltammetry (DPV) techniques is employed for detection of As(III) in de-ionised and lake water. To ensure reliability, rigorous optimization was conducted to achieve near uniformity in the adhesion of the nanomaterial dispersion. The designed sensor's detection limit is 1.12 nM and 0.76 nM for DPV and EIS methods respectively, well below the safe limit of 10 µg/L (∼133 nM). The sensitivity obtained using EIS is 22.5 µM-1 cm-2, and the sensor has a shelf life of 30 days. The proposed methodology can be applied to assess water toxicity without releasing any secondary toxins into the environment and can be coupled with a miniaturized sensing system for enhanced environmental monitoring.

Heavy metal levels in the dairy production chain in China

AbstractThe aims of this study were to investigate the heavy metal pollution status and distribution and to analyze the relationships among metal concentrations of different links in the dairy production chain. Chromium (Cr), arsenic (As), cadmium (Cd), lead (Pb), copper (Cu), and zinc (Zn) levels in water, fodder, milk, blood, hair, and feces samples collected from cows from five dairy farms in China were measured. The concentrations of Cr, As, Cd, Pb, Cu, and Zn were 4.61–11.11, 0.06–0.46, 0.17–0.29, 2.84–4.23, 4.11–7.72, and 7.23–19.91 mg/kg in silage; 12.72–40.85, 0.76–2.40, 0.05–0.16, 4.73–9.16, 44.14–78.46, and 4148.51–4845.20 μg/L in milk; 33.59–60.73, 0.09–3.57, 0.29–1.78, 20.14–39.20, 821.34–1007.45, and 2665.10–4929.95 μg/L in blood; 0.59–1.06, 0.02–0.09, 0.08–0.11, 1.70–2.09, 6.45–8.64, and 9.73–1.56 mg/kg in hair; 31.75–296.35, 0.33–5.96, 0.18–0.53, 3.35–9.06, 12.27–41.39, and 56.54–196.34 mg/kg in feces, respectively. The concentrations of heavy metals in hair were higher than those in the other samples and when combined with the results from the silage and tissue samples, we can assume that cow's hair can be used as a biological indicator for heavy metal contamination in the dairy production chain.

Meta-analysis of the relationship between maternal arsenic exposure and preterm birth

To systematic evaluate the association between maternal arsenic exposure and preterm birth. A literature search was conducted through Pubmed, Web of Science, Embase, China Knowledge Network(CNKI), WanFang Data, Vip Chinese Journal Service Platform(VIP) with a time frame of November 2022 from the beginning of database construction. Meta-analysis of dichotomous variables was performed using Stata MP15 software, and a random or fixed effects model was chosen for the meta-analysis based on the heterogeneity result, with the ratio of ratios(OR) as the effect indicator; subgroup analysis was used to find characteristic changes; funnel plots were used to evaluate publication bias. A total of 15 papers with a sample size of(n=9 892 256 279), 10 prospective cohort studies, 3 retrospective cohort studies, and 2 cross-sectional studies, were included in 6 Chinese and 9 English papers. By Meta-analysis, the combined OR of preterm birth outcome was 1.06(95%CI 1.03-1.09); the result of subgroup analysis by exposure factors and region, the combined OR(95%CI) of hair, blood, urine, drinking water, and placenta were 0.97(0.56-1.69), 1.40(1.22-1.60), 1.04(0.93-1.17), 1.14(1.04-1.24) and 0.69(0.07-6.38). The combined OR(95%CI) were 1.17(1.04-1.31), 1.10(1.05-1.14), 0.69(0.07-6.38) and 1.17(1.01-1.36) for Asia, Americas, Europe and Africa, respectively. For subgroup analysis based on study type, the combined OR(95%CI) was 1.16(1.05-1.28), 1.01(1.01-1.02) and 1.65(0.73-3.74) for prospective cohort studies, retrospective cohort studies, and cross-sectional studies, respectively. Maternal arsenic exposure may contribute to the occurrence of preterm birth, and drinking water arsenic levels may be an important indicator for assessing human arsenic exposure and risk of causing preterm birth.

Neuroprotective effect of quercetin and Zingiber officinale on sodium arsenate-induced neurotoxicity in rats.

The study was aimed at determining the ameliorative potential of quercetin and Zingiber officinale (ZO) against sodium arsenate-induced neurotoxicity in male Wistar rats. Thirty adult animals were randomly allocated to five groups (n=6). Group I served as control, groups II and IV were treated with ZO [300 mg/kg, PO (per os)/day], and group V animals were administered quercetin (50 mg/kg, PO/day) for 18 days. Groups III, IV, and V were injected with sodium arsenate (20 mg/kg, intraperitoneally/day) for 4 days starting from day 15. The administration of sodium arsenate resulted in a significant decrease in total antioxidant status, total thiols, superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, and aryl esterase in brain tissue of the animals compared with the control group. In addition, a significant increase was observed in malondialdehyde, advanced oxidation protein product and plasma nitric oxide levels, indicating oxidative stress-mediated neuronal damage. However, these arsenic-induced alterations were significantly reversed by quercetin or ZO in the treatment groups, indicating their ameliorative potential. These positive effects were further confirmed by histopathological examination of brain tissue revealing the suppression of severe neuronal injury, spongiosis and gliosis in the samples pretreated with quercetin and ZO. Our results suggest that inclusion of ZO and quercetin-rich foods in the diet can help in preventing the neurotoxic effects in areas with elevated levels of arsenic in food chain and ground water.

Association of antibiotics and heavy metal arsenic to horizontal gene transfer from multidrug-resistant clinical strains to antibiotic-sensitive environmental strains.

The emergence of multidrug-resistant bacteria is currently posing a significant threat to global public health. By testing for resistance to different antibiotic classes, we discovered that the majority of clinical bacteria are multidrug-resistant. These clinical multidrug-resistant species have antibiotic resistance genes on their plasmids that can be horizontally transferred to various antibiotic susceptible environmental bacterial species, resulting in antibiotic-resistant transconjugates. Furthermore, we discovered that the presence of an optimal concentration of antibiotics or heavy metal (arsenic) facilitates horizontal gene transfer through the formation of transconjugants. Notably, the addition of a conjugation inhibitor (2-hexadecynoic acid, a synthetic fatty acid) completely blocked the formation of antibiotic or arsenic-induced transconjugants. We discovered a high level of arsenic in water from the Shukratal region, Uttarakhand, India, which corresponded to a high serum level of arsenic in clinically infected individuals from the Shukratal region compared to other locations in Uttarakhand. Importantly, bacterial strains isolated from infected people who drink water from the Shukratal region with high arsenic levels were found to be more antibiotic-resistant than strains isolated from other sites. We discovered that bacterial strains isolated from individuals with high serum arsenic levels are significantly more resistant to antibiotics than individuals with low serum arsenic levels within the Shurkratal. This research sheds light on imminent threats to global health in which improper clinical, industrial, and other waste disposal, increased antibiotic concentrations in the environment, and increased human interference can easily transform commensal and pathogenic bacteria found in environmental niches into life-threatening multidrug-resistant superbugs.

Sodium Arsenite in Drinking Water is a Continuous Threat to Maturing Reproductive System: a Study in Prepubertal Male Mice

Human exposure to arsenic in countries known for heavy arsenic load, where ground water arsenic level exceeds the WHO limit, can be detrimental for developing gonads. Developmental and reproductive toxicity of arsenic in rodents after in utero exposure is although known but information on the toxic effects of arsenic on postnatal gonadal development is scant. This aspect was the focus of the present investigation. Postnatal day 25 prepubertal male mice were challenged with sub-chronic and chronic (up to PND 53 & PND 114 respectively) oral exposure (drinking water) to low and high doses (0.01, 5, and 10 mg.L-1) of sodium arsenite. Data were compared statistically at P<0.05. Sub-chronic exposure to high arsenic doses led to significant increase in the production of reactive oxygen species and lipid peroxidation, while simultaneous significant reduction occurred in the activity of antioxidant enzymes catalase, superoxide dismutase and peroxidase, hormone concentrations (folliclestimulating hormone, luteinizing hormone, testosterone) and sperm parameters. Testicular cell damage and sperm DNA damage, as revealed by comet assay, were evident at 10 mg.L-1arsenic dose. Chronic exposure further aggravated the adverse effects. Severe testicular oxidative stress, reduction in hormones and pronounced histological alterations in testis and epididymis, and sperm parameters together with excessive sperm DNA damage were noticeable even at the lowest test dose of 0.01 mg.L-1. The study concludes that arsenic exposure considerably affects the prepubertal gonad, may cause irreversible damage to the developing reproductive system of males and that minute quantity of arsenic in drinking water can be a serious health hazard.

Testing the Limit: Evaluating Drinking Water Arsenic Regulatory Levels Based on Adverse Pregnancy Outcomes in Bangladesh.

(1) Background: Arsenic (As) is a common drinking water contaminant that is regulated as a carcinogen. Yet, As is a systemic toxicant and there is considerable epidemiological data showing As adversely impacts reproductive health. This study used data from a birth cohort in Bangladesh (2008–2011) to examine associations between drinking water As levels and reproductive outcomes. (2) Methods: Pregnant individuals (n = 1597) were enrolled at <16 weeks gestation and drinking water As was measured. Participants with live births (n = 1130) were propensity score matched to participants who experienced miscarriage (n = 132), stillbirth (n = 72), preterm birth (n = 243), and neonatal mortality (n = 20). Logistic regression was used to examine drinking water As recommendations of 50, 10, 5, 2.5, and 1 µg/L on the odds of adverse birth outcomes. (3) Results: The odds of miscarriage were higher for pregnant women exposed to drinking water ≥2.5 versus <2.5 µg As/L [adjusted odds ratio (OR) 1.90, 95% Confidence Interval (CI): 1.07–3.38)]. (4) Conclusions: These preliminary findings suggest a potential threshold where the odds of miscarriage increases when drinking water As is above 2.5 µg/L. This concentration is below the World Health Organizations and Bangladesh’s drinking water recommendations and supports the re-evaluation of drinking water regulations.

Arsenic-contaminated drinking water and associated health risks in children from communities located in a geothermal site of Michoacán, México: Monte Carlo probabilistic method

Arsenic occurs naturally in ground and spring waters in several geothermal regions in México as a result of natural geochemical processes. Therefore, the goal of this study is to assess the probabilistic health risk in children exposed to arsenic by drinking water from communities located in the geothermal site of Zinapécuaro, Michoacán, México. The water sampling was done monthly for one year and total inorganic arsenic was determined using Hydride Generation coupled with Atomic Absorption Spectrometry. The health risk was assessed using the Monte Carlo probabilistic method. The arsenic levels in water were found to be in the range of 10.4 to 58.9 μg/L, with the highest levels from the hot springs. For children, the 95th percentile of Hazard Index was (HI) >1 for all study sites, with the highest mean (HI = 11 ± 2.9) for Taimeo’s spring water. The ingestion pathway predominantly contributed > 95% to the total health risk in comparison to the dermal exposure route. These results show the potential non-cancerous effects of arsenic in drinking water for children are high. For children and adults, the 95th percentile of Total Cancer Risk (TCR) was 4.7 × 10−4 and 1.2 × 10−3 respectively, exceeding the US EPA safe threshold of 1 × 10−4, which is an unacceptable cancer risk. Sensitivity analysis indicated that arsenic concentration in drinking water, body weight and arsenic intake for children were the most relevant variables on the output parameter HI. Consequently, the environment and health authorities must make greater efforts to provide safe drinking water to protect the residents of Zinapécuaro County.

Concentration level of arsenic in agricultural soil and surface water used for irrigation in Bukuru, JOS- south LGA of plateau state, Nigeria

Arsenic concentration of agricultural soil and surface water used for irrigation were surveyed in two abandoned mining sites of Jos South Local Government Area. DB-Zang and Dorowa total dissolved solid, total hardness, electrical conductivity, temperature and pH of the agricultural soil and surface water were determined according to standard procedure. Result indicates that Total dissolve solids in W1 was 156±2.00mg/L and for W2 (160±2.00mg/L), total hardness W1 (35.20±4.70mg/L) and W2 (44.67±4.70mg/L), electrical conductivity for W1 was 0.240±0.189µs/cm and W2 was 0.120±0.189µs/cm ,electrical conductivity for S1 (0.49±0.16µs/cm), S2 (0.17±0.16µs/cm), temperature for both water was 28.00±0.00oC for soil are 18.00±0.00 o C, pH for W1 (7.10±0.05) and W2 (7.20±0.05), pH for S1 (6.90±0.15) S2 ( 6.60±0.15). The concentration of Arsenic in soil L2 is14.00±0.70µg/kg which is in agreement with WHO recommended level of Arsenic in soil and for L1 257.00±120.00µg/kg which is not in agreement with the WHO recommended level of arsenic, while in water for L1 was 3.00±0.50µg/L which is not in agreement with the WHO recommended level of arsenic and L2 was 48.00±0.70µg/L which is not in agreement with the WHO recommended level of arsenic. The cultivation of food crops in those areas are not recommended.  Â

The Role of Micronutrients and Toxic Metals in the Management of Epidemics in Cambodia.

The illegal trade of wildlife in SE Asia has been identified as the likely cause of the COVID-19 pandemic. We reviewed 198 papers on the current COVID pandemic in Cambodia, diseases such as avian influenza and Nipah virus, most likely to develop into a new pandemic in Cambodia, and common features of disease that require mitigation. Artisanal goldmining uses pure mercury in the areas where wildlife is smuggled to China. Moreover, 30–40% of Cambodians are zinc deficient. High levels of arsenic in irrigation water (>1000 µg/L) are associated with very low levels of zinc in rice (5 µg/g) and rice is the primary staple food for the region. Brown rice from nine of 15 paddy fields in the arsenic zone of Cambodia had double the new guidelines of 100 µg/kg inorganic arsenic for children’s food in the EU and USA. The combination of deficiencies of essential micronutrients like zinc and pervasive presence of arsenic and mercury has the potential to compromise the immunity of many Cambodians. Innovative solutions are suggested to improve micronutrient nutrition. Toxins that suppress the immune system must be better managed to reduce the virulence of pathogens. Cambodia was not likely the source of the COVID-19 but does have problems that could result in a new pandemic.

Assessment of Arsenic Levels in Water, Sediment, and Human Hair around Ie Seu’um Geothermal Manifestation Area, Aceh, Indonesia

The concentration of arsenic in water, sediment, and resident hair in the Ie Seu’um geothermal manifestation area has been analyzed using the Atomic Graphite Furnace Atomic Absorption Spectrophotometry (GF-AAS) method. Sediment and hair samples were prepared by wet digestion using an acid solution. The measurement results were validated by linearity, Limit of Detection (LoD), Limit of Quantification (LoQ), Relative Standard Deviation (%RSD), and %Recovery. The validation test showed that this method is very linear, sensitive, accurate, and precise with a correlation coefficient of 0.9999, LoD of 0.009 μg/L, LoQ of 0.027 μg/L, recovery values of 89.117–101.027% for hair samples and 88.337–105.175% for sediment samples, and RSD of 1.067%. The sample test results showed that the hot springs contained the highest arsenic with levels of 166.73 ± 0.0081 μg/L (IS1). In comparison, the water samples with the lowest arsenic levels were in the rivers that had not been in direct contact with the hot water (IS2) flow, which is 0.80 ± 0.0036 μg/L. All the river water samples that had been in contact with hot water were boreholes, and the resident boreholes located around hot water streams/rivers contaminated with arsenic were above the threshold. Only the river water that had not been in contact with hot water, refill water, and borehole waters outside the hot water flow were detected to be below the threshold level. All the sediment samples showed arsenic contamination, with levels ranging from 2.56–6.86 mg/kg, and it was still within the normal limits recommended by the National Oceanic and Atmospheric Administration (NOAA). Arsenic exposures in communities living around the Ie Seu’um geothermal area, Mesjid Raya Sub-District, Aceh Besar District, Aceh Province, were very high, where 9 out of 10 respondents were positive for arsenic with levels ranging from 54.59–164.57 mg/kg, which was already above the threshold set by the researchers.