There were waterborne diseases such as diarrhoea in Bangladesh due to the drinking of untreated water several decades ago. During the 1970s, UNICEF and some international donor agencies advised the Government of Bangladesh to tap groundwater for drinking purposes. Drinking this groundwater actually reduces the level of diarrhoea, but at the same time it is increasing the risk of arsenic poisoning, leading to arsenicosis,hyperpigmentation, gangrene, and finally cancer.
The latency time of cancer symptoms is 15-30 years depending on arsenic content in the water and the period of ingestion. Local poor people are not actually aware of arsenic poisoning. They still think that tube well water is good quality and that it is much better than the surface water, whether it is contaminated with arsenic or not.