Plant Ecology and Environmental Science Division, CSIR-National Botanical Research Institute, Rana Pratap Marg, Lucknow 226001, India.
Plant Ecology and Environmental Science Division, CSIR-National Botanical Research Institute, Rana Pratap Marg, Lucknow 226001, India.
Environ Int. 2018 Aug;117:327-338. doi: 10.1016/j.envint.2018.05.015. Epub 2018 May 18.
The water quality of Ganga, the largest river in Indian sub-continent and life line to hundreds of million people, has severely deteriorated. Studies have indicated the presence of high level of carcinogenic elements in Ganga water.
We performed extensive review of sources and level of organic, inorganic pollution and microbial contamination in Ganga water to evaluate changes in the level of various pollutants in the recent decade in comparison to the past and potential health risk for the population through consumption of toxicant tainted fishes in Ganga basin.
A systematic search through databases, specific websites and reports of pollution regulatory agencies was conducted. The state wise level of contamination was tabulated along the Ganga river. We have discussed the major sources of various pollutants with particular focus on metal/metalloid and pesticide residues. Bioaccumulation of toxicants in fishes of Ganga water and potential health hazards to humans through consumption of tainted fishes was evaluated.
The level of pesticides in Ganga water registered a drastic reduction in the last decade (i.e. after the establishment of National Ganga River Basin Authority (NGRBA) in 2009), still the levels of some organochlorines are beyond the permissible limits for drinking water. Conversely the inorganic pollutants, particularly carcinogenic elements have increased several folds. Microbial contamination has also significantly increased. Hazard quotient and hazard index indicated significant health risk due to metal/metalloid exposure through consumption of tainted fishes from Ganga. Target cancer risk assessment showed high carcinogenic risk from As, Cr, Ni and Pb as well as residues of DDT and HCHs.
Current data analysis showed that Ganga water quality is deteriorating day by day and at several places even in upper stretch of Ganga the water is not suitable for domestic uses. Although there is positive impact of ban on persistent pesticides with decreasing trend of pesticide residues in Ganga water, the increasing trend of trace and toxic elements is alarming and the prolong exposure to polluted Ganga water and/or consumption of Ganga water fishes may cause serious illness including cancer.
印度次大陆最大的河流恒河，也是数百万人的生命线，其水质已严重恶化。研究表明，恒河水中含有高浓度的致癌元素。
我们对恒河水中的有机、无机污染物和微生物污染的来源和水平进行了广泛的评估，以评估与过去相比，在过去十年中各种污染物的水平变化，以及通过食用恒河盆地受污染鱼类对人口造成的潜在健康风险。
通过数据库、特定网站和污染监管机构的报告进行系统搜索。沿着恒河列出了各州的污染水平。我们讨论了各种污染物的主要来源，特别关注金属/类金属和农药残留。评估了恒河水中有毒物质在鱼类中的生物累积以及通过食用受污染鱼类对人类的潜在健康危害。
在过去十年中（即 2009 年国家恒河流域管理局（NGRBA）成立后），恒河水中的农药水平急剧下降，但一些有机氯的水平仍超过饮用水的允许限值。相反，无机污染物，特别是致癌元素，增加了数倍。微生物污染也显著增加。通过食用受污染的恒河鱼类，金属/类金属暴露的危害系数和危害指数表明存在重大健康风险。目标癌症风险评估表明，砷、铬、镍和铅以及滴滴涕和六氯环己烷的残留具有很高的致癌风险。
目前的数据分析表明，恒河水质正在日益恶化，在一些地方，即使是在恒河上游，水也不适合家庭使用。尽管禁止持久性农药的措施产生了积极影响，恒河水中农药残留呈下降趋势，但痕量和有毒元素的上升趋势令人担忧，长期接触受污染的恒河河水和/或食用恒河鱼类可能会导致严重疾病，包括癌症。
