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During 1998–2000, the authors investigated relations between lung function, respiratory symptoms, and arsenic in drinking water among 287 study participants, including 132 with arsenic-caused skin lesions, in West Bengal, India. The source population involved 7,683 participants who had been surveyed for arsenic-related skin lesions in 1995–1996. Respiratory symptoms were increased among men with arsenic-caused skin lesions (versus those without lesions), particularly “shortness of breath at night” (odds ratio (OR) = 2.8, 95% confidence interval (CI): 1.1, 7.6) and “morning cough” (OR = 2.8, 95% CI: 1.2, 6.6) in smokers and “shortness of breath ever” (OR = 3.8, 95% CI: 0.7, 20.6) in nonsmokers. Among men with skin lesions, the average adjusted forced expiratory volume in 1 second (FEV1) was reduced by 256.2 ml (95% CI: 113.9, 398.4; p < 0.001) and the average adjusted forced vital capacity (FVC) was reduced by 287.8 ml (95% CI: 134.9, 440.8; p < 0.001). In men, a 100-μg/liter increase in arsenic level was associated with a 45.0-ml decrease (95% CI: 6.2, 83.9) in FEV1 (p = 0.02) and a 41.4-ml decrease (95% CI: −0.7, 83.5) in FVC (p = 0.054). Women had lower risks than men of developing skin lesions and showed little evidence of respiratory effects. In this study, consumption of arsenic-contaminated water was associated with respiratory symptoms and reduced lung function in men, especially among those with arsenic-related skin lesions. [ABSTRACT FROM AUTHOR]

There has been widespread speculation about whether nutritional deficiencies increase the susceptibility to arsenic health effects. This is the first study to investigate whether dietary micronutrient and macronutrient intake modulates the well-established human risk of arsenic-induced skin lesions, including alterations in skin pigmentation and keratoses. The study was conducted in West Bengal, India, which along with Bangladesh constitutes the largest population in the world exposed to arsenic from drinking water. In this case-control study design, cases were patients with arsenicinduced skin lesions and had < 500 µg/L arsenic in their drinking water. For each case, an age- and sex-matched control was selected from participants of a 1995-1996 cross-sectional survey, whose drinking water at that time also contained < 500 µg/L arsenic. Nutritional assessment was based on a 24-hr recall for major dietary constituents and a 1-week recall for less common constituents. Modest increases in risk were related to being in the lowest quintiles of intake of animal protein [odds ratio (OR) = 1.94; 95% confidence interval (CI), 1.05-3.59], calcium (OR = 1.89; 95% CI, 1.04-3.43), fiber (OR = 2.20; 95% CI, 1.15-4.21), and folate (OR = 1.67; 95% CI, 0.87-3.2). Conditional logistic regression suggested that the strongest associations were with low calcium, low animal protein, low folate, and low fiber intake. Nutrient intake was not related to arsenic exposure. We conclude that low intake of calcium, animal protein, folate, and fiber may increase susceptibility to arsenic-caused skin lesions. However, in light of the small magnitude of increased risks related to these dietary deficiencies, prevention should focus on reducing exposure to arsenic. [ABSTRACT FROM AUTHOR]

In 1982, Dr. K. C. Saha, a dermatologist of Calcutta, West Bengal, identified patients with skin lesions from the district of 24 Parganas, leading him and others to search for a cause. The cause was soon identified to be arsenic in drinking water, but even today, 20 years later, large number of people continue to drink arsenic contaminated water and patients are increasing in number. Project Well is a program chosen for implementation in some villages of North 24 Parganas. Arsenic safe drinking water is provided for adopted villages by constructing shallow, concrete dugwells designed to tap the water of the unconfined aquifer, 20-30 feet below ground level, that contains low levels (<0.05 mg/L) of arsenic in the target region. The traditional dugwell design is modified by use of tube well hand pumps to withdraw water. The project includes community involvement, programs to increase awareness of the need to drink arsenic safe water, and training in monitoring of dugwell water for arsenic and harmful pathogens. Disinfecting of the water and regulating the water hazard diagram are also included in the training program. The plan is to make the system sustainable at the village level using indigenous labor and materials. [ABSTRACT FROM AUTHOR]

Abstract: Previous studies have suggested that susceptibility to arsenic toxicity could be influenced by micronutrients, in particular selenium, methionine, and beta-carotene. A case–control study was conducted in West Bengal, India, in a region known to have groundwater arsenic contamination, to determine whether differences in micronutrient status contribute to susceptibility to arsenic-induced skin lesions. Micronutrient status was assessed by blood levels of specific micronutrients and metabolic indicators. Blood was obtained from 180 cases with skin lesions and 192 controls. Blood assays measured micronutrients and carotenoids (folate, selenium, vitamin B12, vitamin B6, retinol, alpha-tocopherol, lutein/zeaxanthin, beta-carotene, lycopene, beta-cryptoxanthin) and metabolic indicators such as glucose, cholesterol, transthyretin, amino acids, and proteins potentially associated with methylation (cysteine, homocysteine, methionine, glutathione). The distributions of nutrient concentrations were similar in cases and controls. The median selenium concentrations in cases and controls were both 1.15μmol/L, and there was little evidence of differences in other micronutrients. Odds ratios (ORs) for arsenic-induced skin lesions were estimated for each quartile of nutrient concentrations, using the quartile with the highest nutrient level as the referent group. There were no clear trends associated with deficiencies of any micronutrient or metabolic indicator. For decreasing quartiles of selenium, the OR estimates were 1.00, 0.67, 0.99, 0.80; ; for methionine, the OR estimates were 1.00, 0.83, 0.78, 0.72; . For beta-carotene, the ORs were 1.00, 0.53, 0.51, 0.96, demonstrating no increased risk at the lower quartiles. The measured micronutrients and metabolic indicators investigated do not appear to modify the risk of developing arsenic-induced skin lesions. The lack of any trend of increasing risk with lower selenium, vitamin E, and beta-carotene concentrations has important implications for proposed therapeutic interventions. The emphasis of interventions should be on reducing arsenic exposure. [Copyright &y& Elsevier]

Background: Ingested inorganic arsenic (InAs) is methylated to monomethylated (MMA) and dimethylated metabolites (DMA). Methylation may have an important role in arsenic toxicity, because the monomethylated trivalent metabolite [MMA(III)] is highly toxic., Objectives: We assessed the relationship of creatinine and nutrition--using dietary intake and blood concentrations of micronutrients--with arsenic metabolism, as reflected in the proportions of InAS, MMA, and DMA in urine, in the first study that incorporated both dietary and micronutrient data., Methods: We studied methylation patterns and nutritional factors in 405 persons who were selected from a cross-sectional survey of 7,638 people in an arsenic-exposed population in West Bengal, India. We assessed associations of urine creatinine and nutritional factors (19 dietary intake variables and 16 blood micronutrients) with arsenic metabolites in urine., Results: Urinary creatinine had the strongest relationship with overall arsenic methylation to DMA. Those with the highest urinary creatinine concentrations had 7.2% more arsenic as DMA compared with those with low creatinine (p < 0.001). Animal fat intake had the strongest relationship with MMA% (highest tertile animal fat intake had 2.3% more arsenic as MMA, p < 0.001). Low serum selenium and low folate were also associated with increased MMA%., Conclusions: Urine creatinine concentration was the strongest biological marker of arsenic methylation efficiency, and therefore should not be used to adjust for urine concentration in arsenic studies. The new finding that animal fat intake has a positive relationship with MMA% warrants further assessment in other studies. Increased MMA% was also associated, to a lesser extent, with low serum selenium and folate.

Background: Very little evidence exists concerning the possible impairment of children's intellectual function in relation to arsenic exposure in utero and during childhood., Methods: We conducted a cross-sectional study among 351 children age 5 to 15 years who were selected from a source population of 7683 people in West Bengal, India, in 2001-2003. Intellectual function was assessed with 6 subtests from the Wechsler Intelligence Scale for Children as well as with the Total Sentence Recall test, the Colored Progressive Matrices test, and a pegboard test. Arsenic in urine and lifetime water sources (including during the pregnancy period) were assessed using measurements of samples from 409 wells. The test scores were analyzed with linear regression analyses based on the method of generalized estimating equations incorporating relevant covariates., Results: Stratifying urinary arsenic concentrations into tertiles, we found associations between arsenic and reductions in the adjusted scores of the vocabulary test (0, -0.14, -0.28; P for trend = 0.02), the object assembly test (0, -0.16, -0.24; P for trend = 0.03), and the picture completion test (0, -0.15, -0.26; P for trend = 0.02). These findings correspond to relative declines of 12% (95% confidence interval =0.4% to 24%) in the vocabulary test, 21% (-0.8% to 42%) in the object assembly test, and of 13% (0.3% to 24%) in the picture completion test in the upper urinary arsenic tertile. However, we did not find evidence of an association between test results and arsenic water concentrations during pregnancy or childhood., Conclusions: Current arsenic concentrations in urine, which reflect all sources of recent exposure, including water and food, were associated with small decrements in intellectual testing in school-aged children in West Bengal. We did not see associations between long-term water arsenic concentrations and intellectual function.

Project Well has developed a pilot self-supporting community-based mitigation program to provide arsenic-safe water to the villagers of North 24 Parganas, West Bengal, India. Shallow concrete dugwells, less than 25 feet deep, that tap into an unconfined aquifer are constructed following stipulated guidelines. The design differs from the traditional dugwell in two major ways: (i) there is a layer of coarse sand in the annular space enveloping the outer wall of the concrete cylinder; and (ii) handpumps are used for water extraction to reduce the potential for bacterial contamination. Monitoring programs for arsenic and coliform bacteria in selected dugwells have been completed. In summer, when the water levels were low, the arsenic concentrations were measured. In 11 wells, measured over three years, the average water arsenic concentration was 29 micro gL-1. Two dugwells had high concentrations of arsenic (average 152 micro gL-1 and 61 micro gL-1), but the remaining nine dugwells had an overall average of 11 micro gL-1. Seasonal variation was assessed in five wells with monthly measurements and there was a direct relationship between increases in arsenic concentrations and decreases in the volume of water in the dugwells in the dry summer season. To control bacterial contamination, sodium hypochlorite solution containing 5% chlorine was applied once a month. In 2005, fecal coliform was undetected in 65% (n = 13) of the dugwells but detected at high levels in 35% (n = 7) of the dugwells. The program clearly reduced exposure to arsenic, but we conclude that further study of increases in arsenic concentrations in the dry season are warranted, as well as assessment of ways to more effectively control bacterial contamination such as more frequent chlorination, perhaps with lower doses on each occasion.

The Fogarty International Training and Research Program in Environmental and Occupational Health at UC Berkeley concentrates on two major environmental health issues in the Indian subcontinent: arsenic in drinking water in West Bengal, India, and indoor air pollution in India and Nepal. Local trainees and researchers have had the opportunity to work on related research. Concerning arsenic in drinking water, projects included studies of skin lesions, pulmonary effects, reproductive outcomes, and child development, as well as mitigation approaches to reduce exposures. Activities in the indoor air pollution project have emphasized quantifying exposures to smoke from cooking and heating as well as their associations with tuberculosis and eye disease. Training has focused on developing skills necessary to address these problems. The training emphasizes in-country mentoring of trainees related to their research projects, and intensive short courses at partner institutions. The focus of capacity building in environmental health research in countries in economic and environmental transition should be on country-based research projects with embedded training efforts.

This study was conducted to monitor the changes in arsenic concentration during different seasons in a one-year period during 2002-2003 in selected tubewells in an arsenic-affected area in the district of South 24 Parganas in West Bengal, India, and to map the location of the wells. Seasonal variations in concentrations of arsenic in water were measured from 74 selected tubewells, ranging in depth from 40 to 500 feet. Water samples were collected from these wells during winter, summer, monsoon, and the following winter in 2002-2003. A global positioning system was used for locating the tubewells, and a geographic information system was used for mapping. There was evidence of seasonal variation in concentrations of arsenic in water (p=0.02) with the minimum average concentration occurring in the summer season (694 microg/L) and the maximum in the monsoon season (906 microg/L). From the winter of 2002 to the winter of 2003, arsenic concentrations increased, irrespective of the depth of the tubewells, from an average of 464 microg/L to 820 microg/L (p<0.001). This extent of variation in arsenic concentration, if confirmed, has important implications for both epidemiological research and mitigation programmes.

Background: Over 6 million people live in areas of West Bengal, India, where groundwater sources are contaminated with naturally occurring arsenic. The key objective of this nested case-control study was to characterize the dose-response relation between low arsenic concentrations in drinking water and arsenic-induced skin keratoses and hyperpigmentation., Methods: We selected cases (persons with arsenic-induced skin lesions) and age- and sex-matched controls from participants in a 1995-1996 cross-sectional survey in West Bengal. We used a detailed assessment of arsenic exposure that covered at least 20 years. Participants were reexamined between 1998 and 2000. Consensus agreement by four physicians reviewing the skin lesion photographs confirmed the diagnosis in 87% of cases clinically diagnosed in the field., Results: The average peak arsenic concentration in drinking water was 325 microg/liter for cases and 180 microg/liter for controls. The average latency for skin lesions was 23 years from first exposure. We found strong dose-response gradients with both peak and average arsenic water concentrations., Conclusions: The lowest peak arsenic ingested by a confirmed case was 115 microg/liter. Confirmation of case diagnosis and intensive longitudinal exposure assessment provide the basis for a detailed dose-response evaluation of arsenic-caused skin lesions.

In 1982, Dr. K. C. Saha, a dermatologist of Calcutta, West Bengal, identified patients with skin lesions from the district of 24 Parganas, leading him and others to search for a cause. The cause was soon identified to be arsenic in drinking water, but even today, 20 years later, large number of people continue to drink arsenic contaminated water and patients are increasing in number. Project Well is a program chosen for implementation in some villages of North 24 Parganas. Arsenic safe drinking water is provided for adopted villages by constructing shallow, concrete dugwells designed to tap the water of the unconfined aquifer, 20-30 feet below ground level, that contains low levels (< 0.05 mg/L) of arsenic in the target region. The traditional dugwell design is modified by use of tube well hand pumps to withdraw water. The project includes community involvement, programs to increase awareness of the need to drink arsenic safe water, and training in monitoring of dugwell water for arsenic and harmful pathogens. Disinfecting of the water and regulating the water hazard diagram are also included in the training program. The plan is to make the system sustainable at the village level using indigenous labor and materials.