Saline contamination of drinking water in Bangladesh
Water-related crises are not a new problem in Bangladesh. The discovery of arsenic in drinking water was deemed "the largest mass poisoning of a population in history",1 threatening the lives of millions. Now Bangladesh is facing another environmental and health threat due to man-made and natural factors: increased salinity.
Estimates indicate that Bangladesh has about 2·8 million hectares of land that is affected by salinity—ie, a third of the 9 million hectares of total national cultivated area, and about a fifth of the total area of Bangladesh.2
Saline intrusion from sea water owing to reduction of freshwater flow from upstream (partly owing to the establishment of the Farrakka Barrage on the Ganges near the border of Bangladesh) is expected to be aggravated by climate change and sea-level rises.3 It has already had adverse effects on crop productivity and grain production. Now it appears to be a threat to the wellbeing of communities who live in coastal areas of this low-lying nation.
Increased salinity of drinking water is likely to have a range of health effects, including increased hypertension rates. Large numbers of pregnant women in the coastal areas are being diagnosed with pre-eclampsia, eclampsia, and hypertension. We reviewed hospital records of antenatal check-ups between January and September, 2007, from the Department of Gynaecology in Chalna Upazilla Health Complex—a clinic based in one of the ports in the southwestern region of Bangladesh. Of 561 women undergoing antenatal check-ups, 118 (21%) between the ages of 16 and 40 years were diagnosed with some kind of hypertensive disorder. This rate is strikingly higher than the 2·65% seen in Matuail (Sameena Chowdhury, personal communication), a non-coastal area, and the prevalences of pregnancy-induced systolic and diastolic hypertension of 6·8% and 5·4%, respectively, in another non-coastal rural community of Bangladesh.4
Although local doctors and community representatives have blamed the problem on increased salinity,5 no formal epidemiological study has been done. With both perinatal and maternal mortality remaining persistently high in Bangladesh, an urgent assessment of this situation is warranted.We declare that we have no conflict of interest.
References
1 Smith AH, Lingas EO, Rahman M. Contamination of drinking-water by arsenic in Bangladesh: a public health emergency. Bull World Health Organ 2000; 78: 1093-1103. PubMed
2 Salim M, Maruf B, Chowdhury A, Shamsudoha , Babul A. Increasing salinity threatens productivity of Bangladesh. Dhaka: COAST Trust, 2007. http://www.coastbd.org/Conference%20260507/Pdf%20English/3.pdf. (accessed Dec 20, 2007).
3 Nicholls RJ, Wong PP, Burkett VR, et al. Coastal systems and low-lying areas. Climate change 2007: impacts, adaptation and vulnerability. Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge: Cambridge University Press, 2007.
4 Sayeed MA, Mahtab H, Khanam PA, et al. Diabetes and hypertension in pregnancy in a rural community of Bangladesh: a population-based study. Diabet Med 2005; 22: 1267-1271. CrossRef | PubMed
5 Ministry of Environment and Forest, Government of the People's Republic of Bangladesh. National Adaptation Programme of Action (NAPA). Dhaka: Ministry of Environment and Forest, 2005. http://unfccc.int/resource/docs/napa/ban01.pdf. (accessed Dec 20, 2007).
a Department of Epidemiology and Public Health, Imperial College London, London W2 1PG, UK
b Departments of Gynaecology and Obstetrics, Upazilla Health Complex Dacope, Khulna, Bangladesh
c London School of Hygiene and Tropical Medicine, London, UK
d Grantham Institute for Climate Change, Imperial College London, London, UK
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