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Molecular Nutrition & Food Research | 2009

Status of groundwater arsenic contamination in the state of West Bengal, India: a 20-year study report.

Dipankar Chakraborti; Bhaskar Das; Mohammad Mahmudur Rahman; Uttam Kumar Chowdhury; Bhajan Kumar Biswas; A. B. Goswami; Bishwajit Nayak; Arup Pal; Mrinal Kumar Sengupta; Sad Ahamed; Amir Hossain; Goutam Basu; Tarit Roychowdhury; Dipankar Das

Since 1988 we have analyzed 140 150 water samples from tube wells in all 19 districts of West Bengal for arsenic; 48.1% had arsenic above 10 microg/L (WHO guideline value), 23.8% above 50 microg/L (Indian Standard) and 3.3% above 300 microg/L (concentration predicting overt arsenical skin lesions). Based on arsenic concentrations we have classified West Bengal into three zones: highly affected (9 districts mainly in eastern side of Bhagirathi River), mildly affected (5 districts in northern part) and unaffected (5 districts in western part). The estimated number of tube wells in 8 of the highly affected districts is 1.3 million, and estimated population drinking arsenic contaminated water above 10 and 50 microg/L were 9.5 and 4.2 million, respectively. In West Bengal alone, 26 million people are potentially at risk from drinking arsenic-contaminated water (above 10 microg/L). Studying information for water from different depths from 107 253 tube wells, we noted that arsenic concentration decreased with increasing depth. Measured arsenic concentration in two tube wells in Kolkata for 325 and 51 days during 2002-2005, showed 15% oscillatory movement without any long-term trend. Regional variability is dependent on sub-surface geology. In the arsenic-affected flood plain of the river Ganga, the crisis is not having too little water to satisfy our needs, it is the crisis of managing the water.


Clinical Toxicology | 2005

Murshidabad—One of the Nine Groundwater Arsenic-Affected Districts of West Bengal, India. Part II: Dermatological, Neurological, and Obstetric Findings

Subhash Chandra Mukherjee; Kshitish Chandra Saha; Shymapada Pati; Rathindra Nath Dutta; Mohammad Mahmudur Rahman; Mrinal Kumar Sengupta; Sad Ahamed; Dilip Lodh; Bhaskar Das; M. Amir Hossain; Bishwajit Nayak; Amitava Mukherjee; Dipankar Chakraborti; Subhir Kumar Dulta; Shyamal Kanti Palit; Imrul Kaies; Ajoy Kishore Barua; Khondaker Abdul Asad

Introduction. To understand the severity of related health effects of chronic arsenic exposure in West Bengal, a detailed 3-year study was carried out in Murshidabad, one of the nine arsenic-affected districts in West Bengal. Methods. We screened 25,274 people from 139 arsenic-affected villages in Murshidabad to identify patients suffering from chronic arsenic toxicity for evidence of multisystemic features and collected biological samples such as head hair, nail, and spot urine from the patients along with the tubewell water they were consuming. Results. Out of 25,274 people screened, 4813 (19%) were registered with arsenical skin lesions. A case series involving arsenical skin lesions resulting in cancer and gangrene were noted during this study. Representative histopathological pictures of skin biopsy of different types of lesions were also presented. Out of 2595 children we examined for arsenical skin lesions, 122 (4%) were registered with arsenical skin lesions, melanosis with or without keratosis. Different clinical and electrophysiological neurological features were noticed among the arsenic-affected villagers. Both the arsenic content in the drinking water and duration of exposure may be responsible in increasing the susceptibility of pregnant women to spontaneous abortions, stillbirths, preterm births, low birth weights, and neonatal deaths. Some additional multisystemic features such as weakness and lethargy, chronic respiratory problems, gastrointestinal symptoms, and anemia were also recorded in the affected population. Discussion. The findings from this survey on different health effects of arsenic exposure were compared to those from previous studies carried out on arsenic-affected populations in India and Bangladesh as well as other affected countries. Conclusion. Multisystemic disorders, including dermal effects, neurological complications, and adverse obstetric outcomes, were observed to be associated with chronic arsenic exposure in the study population in Murshidabad, West Bengal. The magnitude of severity was related to the concentration of arsenic in water as well as duration of the exposure.


Journal of Environmental Science and Health Part A-toxic\/hazardous Substances & Environmental Engineering | 2007

Arsenic speciation in rice, straw, soil, hair and nails samples from the arsenic-affected areas of Middle and Lower Ganga plain

E. Sanz; R. Muñoz-Olivas; C. Cámara; M. Kumar Sengupta; Sad Ahamed

In the present study, pressurised liquid extraction and ultrasound probe sonication, for the latter in combination with a mixed enzymatic treatment in case of rice and straw samples, were applied as sample preparation prior to arsenic speciation analysis by high pressure liquid chromatography coupled to inductively coupled plasma mass spectrometric detection (HPLC-ICP-MS). A significant number of samples as different as rice, straw, soil, nail and hair, all coming from the heavily arsenic-contaminated Middle and Lower Ganga plain area, could be investigated with validated methods, supported by high speed extraction methods. For rice and paddy samples, inorganic arsenic counted up to 70–98% of the total arsenic content, being the major species As (III). The levels of arsenic obtained from straw and soil samples are significantly higher than the background levels, being the major species As (V), thus increasing human exposure to arsenic via the soil-plant-animal-human pathway. Concentrations found in hair and nails were significantly higher than their background levels: 39- and 20-fold for hair and nails, respectively. These samples contained mainly inorganic arsenic in its tri- and pentavalent forms. Results indicate that, under the local frame conditions, arsenic mainly enters into the food chain via its more problematic inorganic forms. Arsenic speciation analysis proves to be a powerful tool for a complete analytical assessment in epidemiological studies covering the endemic areas.


Bulletin of The World Health Organization | 2005

Arsenic contamination of groundwater and its health impact on residents in a village in West Bengal, India

Mohammad Mahmudur Rahman; Mrinal Kumar Sengupta; Sad Ahamed; Uttam Kumar Chowdhury; Dilip Lodh; Amir Hossain; Bhaskar Das; Niladri Roy; Kshitish Chandra Saha; Shyamal Kanti Palit; Dipankar Chakraborti

An in-depth study was carried out in Rajapur, an arsenic-affected village in West Bengal, India, to determine the degree of groundwater contamination with arsenic and the impact of this contamination on residents. The flow injection hydride generation atomic absorption spectrometry (FI-HG-AAS) method was used to measure arsenic concentrations in water and biological samples. Dermatologists recorded the dermatological features of arsenicosis. Out of a total of 336 hand-pumped tube-wells in Rajapur, 91% (307/336) contained arsenic at concentrations > 10 microg/l, and 63% (213/336) contained arsenic at > 50 microg/l. The type of arsenic in groundwater, the variation in concentrations of arsenic as the depth of tube-wells changed, and the iron concentration in the wells were also measured. Altogether 825 of 3500 residents were examined for skin lesions; of these, 149 had lesions caused by exposure to arsenic. Of the 420 biological samples collected and analysed, 92.6% (389) contained arsenic at concentrations that were above normal. Thus many villagers might be subclinically affected. Although five arsenic-filtering devices had been installed in Rajapur, it appears that villagers are still exposed to raised concentrations of arsenic in their drinking-water. Detailed village-level studies of arsenic-affected areas in West Bengal are required in order to understand the magnitude of contamination and its effects on people. Villagers are ill-informed about the dangers of drinking arsenic-contaminated water. The contamination could be brought under control by increasing community awareness of the dangers and implementing proper watershed management techniques that involve local people.


Chemosphere | 2016

Arsenic groundwater contamination and its health effects in Patna district (capital of Bihar) in the middle Ganga plain, India.

Dipankar Chakraborti; Mohammad Mahmudur Rahman; Sad Ahamed; Rathindra Nath Dutta; Shyamapada Pati; Subhash Chandra Mukherjee

We investigated the extent and severity of groundwater arsenic (As) contamination in five blocks in Patna district, Bihar, India along with As in biological samples and its health effects such as dermatological, neurological and obstetric outcome in some villages. We collected 1365 hand tube-well water samples and analyzed for As by the flow injection hydride generation atomic absorption spectrometer (FI-HG-AAS). We found 61% and 44% of the tube-wells had As above 10 and 50 μg/l, respectively, with maximum concentration of 1466 μg/l. Our medical team examined 712 villagers and registered 69 (9.7%) with arsenical skin lesions. Arsenical skin lesions were also observed in 9 children of 312 screened. We analyzed 176 biological samples (hair, nail and urine). Out of these, 69 people had arsenical skin lesions and rest without skin lesions. We found 100% of the biological samples had As above the normal levels (concentrations of As in hair, nail and urine of unexposed individuals usually ranges from 20 to 200 μg/kg, 20-500 μg/kg and <100 μg/l, respectively), indicating many people are sub-clinically affected. Arsenical neuropathy was observed in 40.5% of 37 arsenicosis patients with 73.3% prevalence for predominant sensory neuropathy and 26.7% for sensor-motor. Among patients, different clinical and electrophysiological neurological features and abnormal quantitative sensory perception thresholds were also noted. The study also found that As exposed women with severe skin lesions had adversely affected their pregnancies. People including children in the affected areas are in danger. To combat As situation in affected areas, villagers urgently need (a) provision of As-safe water for drinking and cooking, (b) awareness about the danger of As toxicity, and (c) nutritious food.


Clinical Toxicology | 2005

Murshidabad—One of the Nine Groundwater Arsenic-Affected Districts of West Bengal, India. Part I: Magnitude of Contamination and Population at Risk

Mohammad Mahmudur Rahman; Mrinal Kumar Sengupta; Sad Ahamed; Dilip Lodh; Bhaskar Das; M. Amir Hossain; Bishwajit Nayak; Amitava Mukherjee; Dipankar Chakraborti; Subhash Chandra Mukherjee; Shymapada Pati; Kshitish Chandra Saha; Shyamal Kanti Palit; Imrul Kaies; Ajoy Kishore Barua; Khondaker Abdul Asad

Introduction. To understand the severity of the arsenic crisis in West Bengal, India, a detailed, 3-year study was undertaken in Murshidabad, one of the nine arsenic-affected districts in West Bengal. The district covers an area of 5324 km2 with a population of 5.3 million. Methods. Hand tubewell water samples and biologic samples were collected from Murshidabad and analyzed for arsenic by FI-HG-AAS method. Inter laboratory analysis and analyses of standards were undertaken for quality assurance. Results. During our survey we analyzed 29,612 hand tubewell water samples for arsenic from both contaminated and noncontaminated areas, and 26% of the tubewells were found to have arsenic above 50 µg/L while 53.8% had arsenic above 10 µg/L. Of the 26 blocks in Murshidabad, 24 were found to have arsenic above 50 µg/L. Based on our generated data we estimated that approximately 0.2 million hand tubewells are installed in all 26 blocks of Murshidabad and 1.8 million in nine arsenic-affected districts of West Bengal. It was estimated on the basis of our data that about 2.5 million and 1.2 million people were drinking arsenic-contaminated water with concentrations above 10 and 50 µg/L levels respectively in this district. The analysis of total 3800 biologic (nail, urine, and hair) samples from arsenic-affected villages revealed that 95% of the nail and 94% of the urine samples contained arsenic above the normal levels and 75% of the hair samples were found to have arsenic above the toxic level. Thus, many villagers in the affected areas of Murshidabad might be subclinically affected. Discussion and Conclusion. Comparing our extrapolated data with international dose response results, we estimated how many people may suffer from arsenical skin lesions and cancer. Finally, if the exposed population is provided safe water, better nutrition, and proper awareness about the arsenic problem, lives can be saved and countless suffering of the affected population can be avoided.


Journal of Environmental Science and Health Part A-toxic\/hazardous Substances & Environmental Engineering | 2007

Arsenic in the breast milk of lactating women in arsenic-affected areas of West Bengal, India and its effect on infants

Gautam Samanta; Dipankar Das; Badal Kumar Mandal; Tarit Roy Chowdhury; Dipankar Chakraborti; Arup Pal; Sad Ahamed

Two hundred and twenty-six breast milk samples were collected from lactating women from 3 blocks of North-24 Paragans, one of the arsenic-affected districts of West Bengal, India. Out of 226 samples, only in 39 samples arsenic was detected. Urine, hair, and nail samples were also analyzed to know the arsenic body burden of the lactating women. Arsenic in drinking water was also analyzed. Principle component analysis (PCA) revealed that hair and nail arsenic was highly correlated with water arsenic concentrations, whereas arsenic in urine and breast milk did not cluster with water arsenic. Our present study indicated that among the lactating women who had high arsenic body burden and arsenical skin lesions, they had elevated level of arsenic in their breast milk. Arsenic in hair, nails, and urine samples of infants were analyzed, and the results showed significantly high-body burden of infants in those areas. PCA showed the age-dependent relationship between the hair and nail arsenic concentrations of the mothers and their babies.


Archives of Environmental Health | 2003

Groundwater arsenic contamination in the Ganga-Padma-Meghna-Brahmaputra plain of India and Bangladesh.

Mrinal Kumar Sengupta; Amitava Mukherjee; Amir Hossain; Sad Ahamed; Mohammad Mahmudur Rahman; Dilip Lodh; Uttam Kumar Chowdhury; Bhajan Kumar Biswas; Biswajit Nayak; Bhaskar Das; Kshitish Chandra Saha; Dipankar Chakraborti; Subhash Chandra Mukherjee; Garga Chatterjee; Shyamapada Pati; Rabindra Nath Dutta; Quazi Quamruzzaman

magnitude of arsenic groundwater contamination, and its related health effects, in the Ganga-MeghnaBrahmaputra (GMB) plain—an area of 569,749 km2, with a population of over 500 million, which largely comprises the flood plains of 3 major river systems that flow through India and Bangladesh. Design: On the basis of our 17-yr–long study thus far, we report herein the magnitude of groundwater arsenic contamination, its health effects, results of our analyses of biological and food samples, and our investigation into sources of arsenic in the GMB plain Setting: The GMB plain includes the following states in India: Uttar Pradesh in the upper and middle Ganga plain, Bihar and Jharkhand in the middle Ganga plain, West Bengal in the lower Ganga plain, and Assam in the upper Brahmaputra plain. The country of Bangladesh is located in the Padma-Meghna-Brahmaputra plain. In a preliminary study,1 we identified arsenic in water samples from hand-operated tubewells in the GMB plain. Levels in excess of 50 ppb (the permissible limit for arsenic in drinking water in India and Bangladesh) were found in samples from 51 villages in 3 arsenic-affected districts of Uttar Pradesh, 202 villages in 6 districts in Bihar, 11 villages in 1 district in Jharkhand, 3,500 villages in 9 (of a total of 18) districts in West Bengal, 2,000 villages in 50 (of a total of 64) districts in Bangladesh, and 17 villages in 2 districts in Assam. Study Populations: Because, over time, new regions of arsenic contamination have been found, affecting additional populations, the characteristics of our study subjects have varied widely. We feel that, even after working for 17 yr in the GMB plain, we have had only a glimpse of the full extent of the problem. Protocol: Thus far, on the GMB plain, we have analyzed 145,000 tubewell water samples from India and 52,000 from Bangladesh for arsenic contamination. In India, 3,781 villages had arsenic levels above 50 ppb and 5,380 villages had levels exceeding 10 ppb; in Bangladesh, the numbers were 2,000 and 2,450, respectively. We also analyzed 12,954 urine samples, 13,560 hair samples, 13,758 nail samples, and 1,300 skin scale samples from inhabitants of the arsenic-affected villages. Groundwater Arsenic Contamination in the Ganga-Padma-


Toxicological & Environmental Chemistry | 2008

Groundwater arsenic contamination in the Sahibganj district of Jharkhand state, India in the middle Ganga plain and adverse health effects

Bishwajit Nayak; Bhaskar Das; Subhash Chandra Mukherjee; Arup Pal; Sad Ahamed; M. Amir Hossain; Priyanka Maity; Rathindra Nath Dutta; Subir Dutta; Dipankar Chakraborti

A detailed study in the Sahibganj district of Jharkhand state in the middle Ganga plain was carried out to determine the severity of groundwater arsenic contamination and related adverse health effects due to chronic arsenic exposure. Arsenic was analyzed by flow injection hydride generation atomic absorption spectrometry (FI-HG-AAS) in water and biological samples in both contaminated and noncontaminated areas. Health effects in three villages where tubewells (n = 178) were highly contaminated (91, 79.8, and 42% above 10, 50, and 300 µg L−1) were determined. Analyses of a total of 367 biological samples (nail, hair, and urine) from affected villages revealed that an average 88% of samples contained arsenic above normal level. Out of 522 people screened from these three villages, 71 were registered with arsenical skin lesions. A case involving arsenical skin lesions resulting in cancer was noted during the study. A representative histopathological picture of skin biopsy was presented. Out of 40 children examined, nine were registered with arsenical skin lesions. A child of 18 months drinking arsenic concentration water 1150 µg L−1 displayed arsenical skin lesions, indicating arsenical skin lesions may appear earlier if arsenic concentration is high in drinking water. Different clinical and electrophysiological neurological features and abnormal quantitative sensory perception thresholds were noted amongst patients. Provision of safe water, better nutrition, and proper awareness about the arsenic danger to exposed population may save lives and avoid sufferings.


Arsenic Exposure and Health Effects V#R##N#Proceedings of the Fifth International Conference on Arsenic Exposure and Health Effects, July 14–18, 2002, San Diego, California | 2003

Groundwater arsenic exposure in India

Dipankar Chakraborti; Mrinal Kumar Sengupta; Mohammad Mahmudur Rahman; Uttam Kumar Chowdhury; Dilip Lodh; Sad Ahamed; Md. Amir Hossain; G. K. Basu; Subhash Chandra Mukherjee; Kshitish Chandra Saha

Publisher Summary A preliminary study on arsenic (As) in dugwells, hand pumps, and spring water was reported from Chandigarh, and different villages of Punjab, Haryana, and Himachal Pradesh in northern India. It was reported that people were drinking As-contaminated water. High As was found in the liver of those suffering from noncirrhotic portal fibrosis (NCPF) and drinking As-contaminated water. About 1,000 people are suspected to be suffering from arsenical skin lesions from the Semria Ojha Patty village of Sahapur police station in Bhojpur district, Bihar, in the middle Ganga Plain. The magnitude of the problem in Bhojpur district is unknown. Clinical and various laboratory investigations were carried out on 156 patients to ascertain the nature and degree of morbidity and mortality that occurred because of chronic As toxicity in some affected villages. All the patients studied had arsenical skin lesions. Other features included weakness, gastrointestinal symptoms, and involvement of the respiratory system and the nervous system. Lung function tests showed restrictive lung disease, abnormal electromyography, enlargement of the liver, and portal hypertension.

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