Average Arsenic Concentration Research Articles

Drinking water source and exposure to regulated water contaminants in the California Teachers Study cohort.

Pollutants including metals/metalloids, nitrate, disinfection byproducts, and volatile organic compounds contaminate federally regulated community water systems (CWS) and unregulated domestic wells across the United States. Exposures and associated health effects, particularly at levels below regulatory limits, are understudied. We described drinking water sources and exposures for the California Teachers Study (CTS), a prospective cohort of female California teachers and administrators. Participants' geocoded addresses at enrollment (1995-1996) were linked to CWS service area boundaries and monitoring data (N = 115,206, 92%); we computed average (1990-2015) concentrations of arsenic, uranium, nitrate, gross alpha (GA), five haloacetic acids (HAA5), total trihalomethanes (TTHM), trichloroethylene (TCE), and tetrachloroethylene (PCE). We used generalized linear regression to estimate geometric mean ratios of CWS exposures across demographic subgroups and neighborhood characteristics. Self-reported drinking water source and consumption at follow-up (2017-2019) were also described. Medians (interquartile ranges) of average concentrations of all contaminants were below regulatory limits: arsenic: 1.03 (0.54,1.71) µg/L, uranium: 3.48 (1.01,6.18) µg/L, GA: 2.21 (1.32,3.67) pCi/L, nitrate: 0.54 (0.20,1.97) mg/L, HAA5: 8.67 (2.98,14.70) µg/L, and TTHM: 12.86 (4.58,21.95) µg/L. Among those who lived within a CWS boundary and self-reported drinking water information (2017-2019), approximately 74% self-reported their water source as municipal, 15% bottled, 2% private well, 4% other, and 5% did not know/missing. Spatially linked water source was largely consistent with self-reported source at follow-up (2017-2019). Relative to non-Hispanic white participants, average arsenic, uranium, GA, and nitrate concentrations were higher for Black, Hispanic and Native American participants. Relative to participants living in census block groups in the lowest socioeconomic status (SES) quartile, participants in higher SES quartiles had lower arsenic/uranium/GA/nitrate, and higher HAA5/TTHM. Non-metropolitan participants had higher arsenic/uranium/nitrate, and metropolitan participants had higher HAA5/TTHM. Though average water contaminant levels were mostly below regulatory limits in this large cohort of California women, we observed heterogeneity in exposures across sociodemographic subgroups and neighborhood characteristics. These data will be used to support future assessments of drinking water exposures and disease risk.

Evaluation of Heavy Metals Pollution in the Sediments of Diyala River Lower Reaches, Eastern Iraq

Investigating the heavy metals in soil is important to the life of humans and living organisms. Diyala River Lower Reaches was chosen due to the changes in environmental characteristics that took place in recent years. Twelve sediment samples were collected from four different sites. The physical, and chemical properties and the concentrations of nine heavy metals were indicated. The results showed that the average concentrations of arsenic, copper, chromium, cobalt, iron, manganese, nickel, lead, and zinc are 8.5, 45.7, 538.5, 12.2, 5.07, 991.7, 183.5, 16.07, 136.5 ppm, respectively. They reflect contamination with arsenic, chromium, and nickel, while they are free of lead, and zinc contamination, according to the Environmental Protection Agency's (EPA) sediment quality guidelines. The measured contamination indices (the enrichment factor (EF), contamination factor (CF), degree of pollution (Cdeg), geographical accumulation index (Igeo), and pollution load index (PLI)), reflected high contamination factor for arsenic and chromium, and medium for manganese, nickel, lead, and zinc, while low for copper and cobalt. Based on all the results in all sampling sites indicate the presence of heavy element contamination in the sediments of the Diyala River Lower Reaches.

Geochemical Behavior and Enrichment Mechanisms of Arsenic in Low‐Rank Coal, Baiyinhua Depression, Erlian Basin

AbstractIn this study, the abundance of trace elements in Baiyinhua Depression coal and its relationship with the coal depositional environment was examined. (1) The content of arsenic in Baiyinhua Depression coal is that of a typically high arsenic coal from the late Mesozoic of China. The average arsenic content of Baiyinhua coal is 24.93 times, the highest being 132.71 times, that of Chinese coal. Coal rank is not a controlling factor affecting arsenic enrichment in coal. (2) Arsenic is primarily enriched in the syngenetic and diagenetic stages, the enrichment being most obvious in the syngenetic stage, with the intrusion of a magmatic‐hydrothermal solution in the epigenetic stage also providing rich sources of arsenic. (3) The Baiyinhua Coal‐forming plant material is mainly woody plants. The coal seam was covered with deep water, the oxygen supply was very weak, the bacteria very few, the sedimentary environment of the swamp relatively calm and the degree of damage to the woody plants is very low. The minerals in the coal are mainly quartz and clay minerals. The coal ash yield of Baiyinhua is small, with SiO2, Al2O3, MgO, K2O, TiO2, MnO and P2O5 mainly being combined in the inorganic minerals of the coal.

Distribution Characteristics of Arsenic in Drinking Water in China and Its Health Risk Based on Disability-adjusted Life Years

Long-term exposure to arsenic can lead to functional damage to many organs and can be life-threatening. It is of great significance to analyze the distribution characteristics of arsenic in water and evaluate its potential risk for preventing and controlling human health hazards caused by water-derived arsenic. Based on the published data from 2000 to 2022, the geographical distribution characteristics of arsenic in drinking water across China were systematically analyzed in detail, and the health risk of arsenic in drinking water was quantitatively assessed using disability-adjusted life years (DALYs), which represent the burden of disease. The results showed that the average concentration of arsenic in drinking water in China was (2.88 ±0.33) μg·L-1, which was lower than the limit of 10 μg·L-1 set by the standard for drinking water quality (GB 5749-2022). Nevertheless, the arsenic in drinking water in some provinces, including Shanxi, Inner Mongolia, and Ningxia, was still higher than the limit. The arsenic concentration in drinking water in northern China was higher than that in southern China, and that in rural areas was higher than that in cities. The estimated health risk of arsenic in drinking water (1.63×10-6 DALYs per person-year) was higher than the acceptable risk level of waterborne exposure of 1.0×10-6 DALYs per person-year set by the World Health Organization. The personal health risks related to arsenic in drinking water in the six geographical regions were ranked as follows:North China > Northeast China > Central South China > Northwest China > Southwest China > East China. Almost all (99.4%) of the health burden associated with water arsenic was attributable to skin and lung cancer, which caused 2 905.25 and 1 513.96 DALYs per year, respectively. Most (78.0%) of the health burden was borne by people aged 45 years or older. In addition, given the proportion of each age group in the total population, older persons over the age of 60 bear a higher drinking-water-associated arsenic burden at the individual level than others, and attention should be consequently paid to them when controlling the risk of arsenic in water.

Worldwide arsenic levels in human breast milk and probabilistic health risk assessment: A systematic review and meta-analysis

Background: The exposure to toxic metals is a major global health concern due to their stability, bioaccumulation, and high toxicity. These metals can be transmitted to the fetus through the placenta and exposure can last throughout life. This systematic review focused on the potential risks of arsenic (As) in breast milk to newborns and infants. Methods: Multiple keywords, such as "human milk" and "breast milk", associated with "toxic metal", "heavy metal" or "arsenic" were used to search related databases. Of the 151 articles found, 45 studies were eligible for qualitative review, and 34 were included in the meta-analysis. Results: The lowest and highest levels of arsenic were found to be 0.04±0.70 and 27.75±28.30 μg/L, respectively. The overall pooled average concentration (95% CI) of arsenic in breast milk was 0.11 (95% CI: 0.11, 0.12). The results indicated that infants who consume breast milk are within a safe limit for cancer risk. Conclusion: The exposure to significant metals is associated with disease development. Therefore, ongoing knowledge creation through mental acts and continuous observation is necessary to better understand the effects of heavy metals in future studies.

Prediction of human health risk and disability-adjusted life years induced by heavy metals exposure through drinking water in Fars Province, Iran

Exposure to heavy metals in contaminated drinking water is strongly correlated with various cancers, highlighting the burden of disease. This study aimed to assess the non-carcinogenic and carcinogenic risks associated with exposure to heavy metals (As, Pb, Cd, and Cr) in drinking water of Fars province and evaluate the attributed burden of disease. Non-carcinogenic risk assessment was performed using the hazard quotient (HQ) method, while the carcinogenic risk assessment utilized the excess lifetime cancer risk approach. The burden of disease was evaluated in terms of years of life lost, years lived with disability, and disability-adjusted life years (DALY) for three specific cancers: skin, lung, and kidney cancer. The average drinking water concentrations of arsenic (As), cadmium (Cd), chromium (Cr) and lead (Pb) were determined to be 0.72, 0.4, 1.10 and 0.72 μg/L, respectively. The total average HQ of heavy metals in drinking water in the study area were 0.127, 0.0047, 0.0009 and 0.0069, respectively. The average ILCRs of heavy metal in the entire country were in the following order: 1.15 × 10−5 for As, 2.22 × 10−7 for Cd and 3.41 × 10−7 for Cr. The results also indicated that among the various counties analyzed, Fasa experiences the greatest burden of disease in terms of DALYs, with a value of 87.56, specifically attributed to cancers caused by exposure to arsenic. Generally, it can be said that the burden of disease is a critical aspect of public health that requires comprehensive understanding and effective intervention.

Superfood consumers' exposure to selected heavy metals.

Background: Superfood products are important components of the human diet, which may contain toxic heavy metals that have no beneficial function in the human body (e.g., cadmium, arsenic, mercury). Therefore, due to the high demand for these foods, maintaining their safety is a significant public health concern, resulting in an increasing number of studies in the field of health risk assessment due to population exposure to heavy metals. Aim: The aim of the study was to determine the concentration of selected heavy metals in individual superfood products. Methods: The research material consisted of 48 samples of selected superfood products such as flaxseed, chia seed, black cumin, goji berries, buckwheat, millet, almonds, quinoa and green tea. The collected samples were subjected to the mineralization process. In addition, an exposure assessment was performed by calculating the hazard quotient (HQ). Statistical analysis was performed using Statistica software for cadmium and arsenic. Results: The highest level of cadmium was observed in a sample of flaxseed (ground)-0.35 mg/kg. Again, the highest concentration of arsenic was found in green tea bags (21.94 mg/kg). The exposure assessment showed that the risk of adverse health effects is likely to occur with the consumption of flaxseed, almonds, quinoa and green tea at both the assumed average and maximum arsenic concentrations (HQ > 1). Conclusions: There are many foods on the market that contain heavy metals. The accumulation of various heavy metals in agricultural soils and edible crops should be regularly assessed to minimize public health problems.

Geochemical evaluation and environmental risk assessment of heavy metals: A case study from Ireland using Tellus stream sediment data (2011–2017)

A comprehensive assessment of the distribution, spatial mapping and ecological risk of heavy metals in stream sediments of 17 counties of Ireland based on the Tellus geochemical survey programme in Ireland was carried out. Average trace metal concentrations of chromium (Cr), nickel (Ni), copper (Cu), lead (Pb), zinc (Zn), vanadium (V), cobalt (Co), arsenic (As), and major and minor oxides iron oxide (Fe2O3), manganese oxide (MnO) in the stream sediments were above the background values, but lower than Irish sediment quality guidelines for livestock and Canadian sediment quality guidelines (ISQG); threshold effect level (TEL) and probable effect level (PEL). 69.65% of Ni, 22.13% of Zn, and 96.7% of Pb samples exceeded the low-effect-range (ERL) values, whereas only 21%, 1.80% and 0.69% of the same elements exceeded the median effect range (ERM) values. Hotspots of Zn (>12000 mg kg−1), Pb (>10,000 mg kg−1), Fe2O3 (61.38%), MnO (26%), Cr (>2300 mg kg−1) and Ni (874.2 mg kg−1) were observed at Wicklow, Dublin, Mayo, Galway and Cavan counties. Catchment geochemistry was identified for the presence of heavy metals in the stream sediments. The geo-accumulation index (Igeo) indicated Kildare to be the least contaminated county with Igeo < 0 for Cr, Ni, Cu, Zn, Pb and As for 50% of the samples. The enrichment factor (EF) indicated that some sites located in Mayo and Donegal were highly contaminated. PInemerow followed the trend, Tipperary > Dublin > Waterford > Monaghan > Donegal > Wexford > Galway > Wicklow > Cavan > Meath > Kilkenny > Leitrim > Mayo > Louth > Sligo > Kildare > Carlow. Based on potential ecological risk index (PERI), 83.1% of the sites posed low ecological risk (PERI <150), 11.9% sites posed moderate risk (150 < RI < 300) and high ecological risk was posed by 0.3% (PERI >1200) of the sites. Lithology, topography and anthropogenic factors influenced the distribution and ecological risks of heavy metals. Non-carcinogenic and carcinogenic risk for adults and children were above the recommended value.

Determination of metal(oids) in different traditional flat breads distributed in Isfahan city, Iran: Health risk assessment study by latin hypercube sampling.

This survey was conducted to assess the metal(oids) content in 93 samples of bread, including barbari, lavash, and tafton, using inductive couple plasma/optical emission spectroscopy (ICP-OES) method and atomic absorption spectroscopy (AAS). The amounts of measured element were compared with the permissible limit set for bread by FAO/WHO and Iranian National Standardization Organization (INSO). The limit of detection (LOD) was ranged from 6.6 × 10-5 to 2.1 × 10-2 mg l-1 with recoveries ranged from 92% to 102%. The average concentrations of aluminum (Al), arsenic (As), boron (B), cadmium (Cd), iron (Fe), mercury (Hg), magnesium (Mg), sodium (Na), lead (Pb), and zinc (Zn) in bread were 29.88 ± 8, 0.03 ± 0.004, 12.77 ± 3.70, 0.01 ± 0.006, 34.16 ± 8.95, 0.01 ± 0.008, 346.07 ± 36.08, 3314.81 ± 317.19, 0.24 ± 0.11, and 19.65 ± 4.66 mg Kg-1, respectively. Amounts of As, Cd, Hg, Mg, Pb, and Zn were lower, and those of Al, Fe, and Na were higher than the permissible limits defined by FAO/WHO. The Latin Hyper Cube (LHC) sampling results revealed that children were exposed to higher non-carcinogenic risk and adults were more threatened by carcinogenic risk. It is recommended to control the entrance of metals in bread in the farm-to-fork chain in order to prevent probable future health challenges.

Modified oyster shell powder with iron (II) sulfate heptahydrate to improve arsenic uptake in solution and in contaminated soils.

Arsenic is a metalloid whose presence can be due to natural or anthropological causes. It is considered as a toxic chemical that puts human health at high risk. In this study, we evaluated a novel modified oyster shell (MOS) that was coated with iron (II) sulfate heptahydrate using two different proportions through batch sorption experiments in an arsenic solution and in arsenic-contaminated soils. The arsenic solution was prepared using As(III)-standard solution. The arsenic contaminated soils were extracted from a contaminated site in Cheonan, South Korea, where the average arsenic concentration of the soil was reported as 136.28mg/kg. Different doses of oyster shell and modified oyster were used to understand the effect of the addition of iron (II) sulfate heptahydrate via sorption batch experiments in solution and sorption tests in soils. The sorption tests were conducted with 50g of contaminated soil; then, 150g of soils was used for the pot cultivation tests, and finally, 150g of contaminated soils was used for column percolation test. Through the experiments, the authors observed a comparable improvement of arsenic stabilization from 10 to 60% with the addition of iron (II) sulfate heptahydrate to oyster shell.

Synergy of arsenic with smoking in causing cardiovascular disease mortality: A cohort study with 27 follow-up years in China.

To explore the patterns of the exposure-response relationship between arsenic exposure and cardiovascular disease (CVD) mortality and investigate the effect of cigarette smoking on the association. Seven thousand seven hundred thirty-five tin miners with at least 10 years of arsenic exposure were enrolled since 1992 and followed up for 27 years. Each individual's air arsenic exposure at workplace was calculated by time weighted average arsenic concentration × exposure months. Detailed information on smoking was collected at baseline, and information on smoking status was collected for five consecutive years from 1992 to 1996. Hazard ratio (HR) and 95% confidence interval (CI) for the risk of CVD were estimated using Cox proportional hazards models. A total of 1,046 CVD deaths occurred in this cohort over 142,287.7 person-years of follow up. We firstly reported that for equal cumulative exposure, participants exposed to higher concentrations over shorter duration had a higher risk of CVD mortality than those exposed to lower concentration over longer duration. The HR and 95% CI were 1.38 (95%CI: 1.03-1.85) in participants exposed to arsenic concentration (45.5-99.5 mg/m3), 1.29 (95%CI: 1.02-1.67) in 99.5-361.0 mg/m3. Further, participants with age at first exposure <18 years had a significantly higher risk of morality from CVD, cerebrovascular and heart diseases than those with ≥18 years. Finally, all synergy indices were greater than 1 (range, 1.11-2.39), indicating that the joint effect of arsenic exposure and cigarette smoking on CVD mortality was greater than the sum of their individual effect. Exposure to air arsenic at workplace is adversely associated with mortality from CVD, especially among smokers younger than 18 years and smokers.

A COMPARATIVE RISK ASSESSMENT OF HAZARDOUS TOXIC AND POTENTIALLY TOXIC ELEMENTS GENERATING FROM COAL FIRED POWER PLANT AND WASTE WATER TREATMENT PLANT, THAILAND

Fly ash from Mae Moh power plant in Lampang province, northern Thailand (unit 6, 8, 10 and 11) was investigated to find out the heavy metals (As, Cd, Hg, Pb and Zn) content of fly ash. Every metal content except mercury is at higher level than the background soil. The average arsenic content was two times higher than the background soil and unit 11 contains the largest amount of arsenic (148.5 mg kg-1). Mercury content of fly ash in the dumping site was not detectable. Sludge, end product of wastewater treatment plant, from Nong Kaem wastewater treatment plant was also investigated. The average arsenic content was higher in fly ash (89.56 mg kg-1) than sludge (22.01 mg kg-1) whereas cadmium, lead, zinc and mercury content was higher in sludge (0.56, 306.07, 1963.23 and 3.97 mg kg-1 respectively) than fly ash (0.46, 10.07, 90.73 and 0 mg kg-1).

Essential and Non-Essential Elements in Razor Clams (Solen marginatus, Pulteney, 1799) from the Domitio Littoral in Campania (Southwestern Tyrrhenian Sea, Italy).

The levels of essential (Cu, Cr, Co, Mn, Se, Zn) and non-essential (As, Be, Bi, Cd, Cs, Ga, Ni, Pb, Sr, Tl, U, V) trace elements were studied in razor clams (Solen marginatus) collected from the Tyrrhenian coast of Southern Italy at five selected sites along the Domitio littoral in the Campania region. The main objectives of this study were to assess the contamination status of these bivalve mollusks and to evaluate the risks to the environment and consumers due to metal contamination. The concentrations of 18 trace elements were determined after microwave-assisted mineralization and by inductively coupled plasma mass spectrometry (ICP-MS). Concentrations of the toxic elements Pb and Cd were below the maximum levels established by Commission Regulation (EC) 1881/2006, while higher average concentrations of arsenic were found at each of the five sites studied. Regarding the other trace elements, contamination levels followed the order: Zn > Sr > Mn > Cu > Se > Cr > V > Ni > Co > Ga > Cs > Be > U > Bi > Tl. No significant differences among the sites were found with regard to any of the trace elements analyzed, and element levels in razor clams did not reflect sediment contamination. The results demonstrated the substantial food safety of the razor clams in this area with respect to heavy metals but revealed a potential health risk due to arsenic contamination in all the areas sampled.

Heavy metals in soil-like material from landfills – Resource or contaminants?

In the last decade landfill mining (LFM) has gained particular attention due to the possibility of resource recovery from landfills. However, landfills consist mainly of soil-like material (SLM) which is of little or no economic value. The aim of the present study is to provide a global overview of SLM in terms of heavy metal concentrations and its resource potential. As references for the resource assessment served metal concentrations in ores, thresholds for compost and earthworks, and abundance in Earth's crust. The preparation of a meta-analysis included 573 chemical analyses from 59 landfills in 12 countries. Average concentrations of arsenic, zinc and nickel turned out to be quite similar worldwide, whereas those of lead, copper and mercury showed remarkable differences between the landfills. Chromium, nickel, lead and zinc concentrations proved to exceed most likely compost, while arsenic and mercury concentrations remained usually below thresholds. With regard to a reuse of SLM in earthworks, elevated zinc concentrations were most of concern, followed by lead, copper, chromium and cadmium. However, chromium and nickel concentrations were found to be most similar to abundances in Earth's crust. Heavy metal concentrations in SLM were worldwide not comparable to those found in ores. Moreover, we observed that the option of multiple metal recovery did not improve significantly the resource potential.

Toxic elements in Sardina pilchardus and food toxicological significance

ABSTRACT Cd, Hg, and Pb concentrations were investigated in Sardina pilchardus fish. Samples originated from the Atlantic Northeast fishing area 27 and were analysed by inductively coupled plasma optical emission spectroscopy. The aim of the study was to estimate the health impact of consumption, based on the concentrations and calculated exposure for each element. Based on the average total arsenic concentration of 3.26 ± 0.39 mg/kg in the samples, the estimated inorganic arsenic content and calculated PTWI suggested that the samples do not pose a health risk for consumers. Cadmium content of the samples was also not considered hazardous, as both the measured concentrations and PTMI values were below the specified limits. Lead concentration exceeded the maximum limit in 73% of the samples, while calculated average weekly intake was below the recommended level. The measured mercury concentrations exceeded the maximum limit in only 5% of the samples.

Assessment of burden of disease induced by exposure to heavy metals through drinking water at national and subnational levels in Iran, 2019.

The burden of disease attributable to exposure to heavy metals via drinking water in Iran (2019) was assessed at the national and regional levels. The non-carcinogenic risk, carcinogenic risk, and attributable burden of disease of heavy metals in drinking water were estimated in terms of hazard quotient (HQ), incremental lifetime cancer risk (ILCR), and disability-adjusted life year (DALY), respectively. The average drinking water concentrations of arsenic (As), cadmium (Cd), chromium (Cr), lead (Pb), mercury (Hg), and nickel (Ni) in Iran were determined to be 2.3, 0.4, 12.1, 2.5, 0.7, and 19.7μg/L, respectively, which were much lower than the standard values. The total average HQs of heavy metals in drinking water in the entire country, rural, and urban communities were 0.48, 0.65 and 0.45, respectively. At the national level, the average ILCRs of heavy metal in the entire country were in the following order: 1.06×10-4 for As, 5.89×10-5 for Cd, 2.05×10-5 for Cr, and 3.76×10-7 for Pb. The cancer cases, deaths, death rate (per 100,000 people), DALYs, and DALY rate (per 100,000 people) attributed to exposure to heavy metals in drinking water at the national level were estimated to be 213 (95% uncertainty interval: 180 to 254), 87 (73-104), 0.11 (0.09-0.13), 4642 (3793-5489), and 5.81 (4.75-6.87), respectively. The contributions of exposure to As, Cd, Cr, and Pb in the attributable burden of disease were 14.7%, 65.7%, 19.3%, and 0.2%, respectively. The regional distribution of the total attributable DALY rate for all heavy metals was as follows: Region 5> Region 4> Region 1> Region 3> Region 2. The investigation and improvement of relatively high exceedance of As levels in drinking water from the standard value, especially in Regions 5 and 3 as well as biomonitoring of heavy metals throughout the country were recommended.

Aqueous Arsenic Speciation with Hydrogeochemical Modeling and Correlation with Fluorine in Groundwater in a Semiarid Region of Mexico

In arid and semiarid regions, groundwater becomes the main source to meet the drinking water needs of large cities, food production, and industrial activities. For this reason, necessary studies must be carried out to estimate its quantity and quality, always seeking sustainable management, thus avoiding social conflicts or a decrease in the productive activities of humanity. This research explains the behavior of groundwater quality concerning arsenic speciation and its relationship with fluoride. The average total arsenic concentration of 19.95 µg/L and 20.29 µg/L is reported for the study period from 2015 to 2020, respectively, according to the Mexican standard. If the population drinks water directly, it is exposed to possible damage to health. The predominant arsenic species is As (V), with 95% and As (III) with 5%, this finding will allow us to define in greater detail the type of remediation that is required to reduce the content of this element in the water. Regarding the relationship between arsenic and fluorine, very small Pearson correlation coefficients of the order of 0.3241 and 0.3186 were found. The estimation of the space–time variation made it possible to identify the areas with the highest concentration of arsenic and fluorine, allowing the definition of the operating policies of these wells, thereby protecting the health of the inhabitants who consume this water.

The toxicokinetic of arsenic in the edible and non-edible tissues of freshwater shellfish

Although the chemical speciation and distribution characteristics of arsenic in freshwater shellfish have been adequately studied, little is known about the differences in arsenic speciation and bioaccumulation in the edible and non-edible tissues. In this study, we collected Parafossarulus eximius from the Xiang River, which is heavily polluted by mining activities in China. The levels of arsenic species in the shellfish specimens were determined using HPLC-ICP-MS. The average concentration of total arsenic (tAs) in the muscle of dried shellfish was 9.934 ± 7.173 mg ⋅ kg −1 . As(V) and arsenobetaine were the dominant chemical species in the collected samples. Correlations analysis showed that As concentration in sediments directly affects the As concentration in shellfish, especially the non-edible part. A significant correlation between As(III) and As(V) in the edible and the non-edible parts was observed, suggesting a mutual transformation between the two species. Further results from the correlation analysis indicated that when the intake of inorganic arsenic (iAs) by shellfish was high, the biological transformation process from iAs to AsB reached a saturation. The chronic health risk for consumers from P. eximius was not observed. Whereas, continuous consumption would pose considerably carcinogenic risk. • Shellfish from the Xiang River was heavily polluted by mining activities. • As(V) and AsB were the dominant chemical species. • As concentration in sediments directly affects the As concentration in shellfish. • The biological transformation of iAs to AsB has a threshold value. • Continuous consumption of P. eximius would pose considerably to local consumers.

Health Risk Assessment of Arsenic in the Drinking Water of Upper Sindh, Pakistan

Water is a valuable compound for plants, animals, and humans. Various contaminating agents pollute it, with arsenic being one of them. Measurements of arsenic in potable water in Upper Sindh were conducted during this study. The samples were prepared by microwave-assisted digestion and analyzed by an atomic absorption spectrophotometer. A total of 240 potable water samples were collected from 8 Talukas of Upper Sindh. DMS coordinates were also recorded with the help of the Global Positioning System (GPS). The highest arsenic content of 50µg/L was observed in Garhi Khairo Taluka. The average arsenic content in water samples of all of the Talukas, except Miro Khan, was found higher than the WHO permissible limit. The 69.2% of samples were found to be contaminated by arsenic. Therefore, the water of the studied area is concluded to be in poor condition for cooking and drinking.

Arsenic geochemistry of the sediments of the shallow aquifer and its correlation with the groundwater, Rangpur, Bangladesh

The geochemical analysis of the shallow aquifer sediments of the area of investigation reveals that they are acidic in nature. The mean electrical conductivity of the deposits is 1.16 dS/m that indicates very low or negligible effects of salinity of the sediments of the Rangpur division. The median values of the concentrations of total organic carbon, total nitrogen and sulphur are 0.20%, 0.02% and 58.68 mg/kg, respectively. The trend of the average heavy metal concentrations of the investigated area can be shown as Fe > As > Cu > Zn. The average concentrations of arsenic of the sediments of the study area are 3.52 mg/kg. Sulphur is significantly, positively correlated with copper and zinc (p < 0.05) and insignificantly and positively correlated with arsenic content of the sediments that indicates that the copper and zinc occur as sulphide minerals. The mean concentrations of arsenic in the groundwater are 1.1793 μg/L. The concentration of all the water samples is below the permissible limit of World Health Organization (10 μg/L). The arsenic content of groundwater shows the positive correlations with the arsenic, iron and copper concentrations of the sediments. This implies that the arsenic of groundwater derived from the geogenic source, like the dissolution of arsenic bearing minerals of the aquifer sediments—pyrite and arsenopyrite. The acidic nature, texture and minor quantities of total organic carbon are the factors that also influence the low arsenic enrichment in the investigated sediments and its release to the groundwater. The contemporary arsenic specification research works showed that As(III) the most common species in natural water and foodstuffs and the arsenic is inorganic from source in Bangladesh.