Groundwater Arsenic Contamination in the Ganga-Padma-Meghna-Brahmaputra Plain of India and Bangladesh

• Published in: Archives of environmental health Vol. 58; no. 11; pp. 701 - 702
• Main Authors: Sengupta, Mrinal K., Mukherjee, Amitava, Hossain, Md A., Ahamed, Sad, Rahman, Mohammad M., Lodh, Dilip, Chowdhury, Uttam K., Biswas, Bhajan K., Nayak, Biswajit, Das, Bhaskar, Saha, Kshitish C., Chakraborti, Dipankar, Mukherjee, Subhash C., Chatterjee, Garga, Pati, Shyamapada, Dutta, Rabindra N., Quamruzzaman, Quazi
• Format: Journal Article
• Language: English
• Published: Washington, DC Heldref 01.11.2003
• Subjects: Adult; Arsenic - analysis; Arsenic - toxicity; Arsenic - urine; Arsenic Poisoning - complications; Arsenic Poisoning - epidemiology; Arsenic Poisoning - pathology; Bangladesh; Biological and medical sciences; Chemical and industrial products toxicology. Toxic occupational diseases; Child; Child, Preschool; Crops, Agricultural; Developing Countries; Environment. Living conditions; Female; Fresh Water - analysis; Hair - chemistry; Housing. Living conditions; Humans; India; Infant; Infant, Newborn; Medical sciences; Metals and various inorganic compounds; Nails - chemistry; Pregnancy; Pregnancy Complications - epidemiology; Pregnancy Outcome; Public health. Hygiene; Public health. Hygiene-occupational medicine; Rural Population; Skin - chemistry; Skin - pathology; Toxicology; Tropical medicine; Water Pollution, Chemical - analysis; Water Supply - analysis; Asia; Bangladesh; India; India, Assam; India, Bihar; India, Jharkhand; India, West Bengal; India, Uttar Pradesh; Concentration measurement; Drinking water; Chemical analysis; Arsenic; Content; Developing countries; Public health; Quantitative analysis; Chemical contamination; Ground water
• ISSN: 0003-9896; 2331-4303
• DOI: 10.3200/AEOH.58.11.701-702

Objective: This report is presented to highlight the magnitude of arsenic groundwater contamination, and its related health effects, in the Ganga-Meghna-Brahmaputra (GMB) plain--an area of 569,749 km super(2), 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, 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. In addition, our medical group examined 142,000 individuals, including children (age range: infants to 11 yr), for arsenic toxicity. We studied 2,235 borehole sediment samples to investigate possible mineralogical origins of arsenic contamination. We also analyzed 30 vegetable and 8 paddy rice samples for total arsenic and arsenic species, from 3 villages in which arsenic-contaminated groundwater was used for cultivation. In performing our analyses to identify arsenic species in water, urine, and food, we used methodologies such as flow injection hydride generation atomic absorption spectrometry (FI-HG-AAS), ion chromatography inductively coupled plasma mass spectrometry (IC-ICP-MS), high-performance liquid chromatography/inductively coupled plasma mass spectrometry (HPLC-ICP-MS), electron probe microanalysis (EPMA), laser microprobe mass analysis (LAMMA), x-ray fluorescence spectroscopy (XRF), and x-ray diffraction (XRD). Results: In India, 48.7% of water samples tested had arsenic concentrations above 10 ppb (the World Health Organization's guideline value for arsenic in drinking water). This proportion of samples would potentially affect nearly 9 million people. In addition, 23.8% of samples exceeded 50 ppb arsenic (the standard followed in most developing countries), exposing 7 million people to this level of contamination. In Bangladesh, 43.0% of water samples exceeded 10 ppb and 31.0% exceeded 50 ppb. The affected populations were 52 and 32 million, respectively. Almost 9.89% (n = 123,000) of the patients screened from India showed skin lesions; in Bangladesh the ratio was 19.8% (n = 19,000). In children, these numbers were 2% from India (n = 15,000) and 6.1% (n = 5,000) from Bangladesh. Various types of skin manifestations of arsenic toxicity were observed--from melanosis, keratosis, hyperkeratosis, dorsal keratosis, and nonpitting edema, to gangrene and cancer. Arsenic neuropathy, as well as adverse pregnancy outcomes such as spontaneous abortion, stillbirth, preterm birth, and low birth weight, were also recorded. The normal level of arsenic in hair ranges from 80-250 mu g/kg (levels greater than or equal to 1,000 mu g/kg indicate toxicity). In nails, normal levels range from 430-1,080 mu g/kg. Normal excretion of arsenic in urine ranges from 5-40 mu g per 1.5 l per day. In India, in our study, 62% of hair samples contained toxic levels of arsenic; 83% of nail samples and 88% of urine samples showed arsenic above normal levels. In Bangladesh, the ratios were 83%, 93%, and 95%, respectively. Consequently, a considerable proportion of the population could be affected subclinically. Studies of borehole sediments showed the presence of arsenic in pyrite and in iron oxyhydroxide. The speciation studies of food samples from the affected villages revealed that most of the arsenic in rice and vegetables was in inorganic form. Conclusions: In the GMB plain of India and Bangladesh--a 569,749 km super(2) area with a population of more than 500 million--nearly half the land area and inhabitants may be at risk from groundwater arsenic contamination. Progress toward resolution of this crisis in the GMB plain will require proper watershed management, economical utilization of available surface water, and the participation of all who live in, or have influence over, the region.