Severe groundwater contamination has led to congenital deformities among people living in some parts of the northern Indian state of Punjab.
Research over a two-year period found that poisonous pesticides and heavy metals had entered the food chain.
Apart from deformities, cancer and kidney damages are also reported.
The study was commissioned by the Punjab Water Pollution Control Board, which told the BBC it was studying the findings.
The study - by a team of senior doctors from the post-graduate Institute of Medical Education in Chandigarh - was conducted over the past two years.
It linked contaminated water with varying degrees of DNA mutation in people in the state.
According to the study, 80 per cent of ground water samples had mercury that was far beyond the permissible level.
Arsenic was found in 70 per cent of samples of effluent, 50 per cent of tap water samples and 57.7 per cent of ground water samples.
Arsenic is a semi-metal element that enters drinking water supplies from natural deposits in the earth or from agricultural and industrial practices.
Non-cancer effects can include thickening and discoloration of the skin, stomach pain, nausea, vomiting; diarrhea; numbness in hands and feet; partial paralysis; and blindness. Arsenic has been linked to cancer of the bladder, lungs, skin, kidney, nasal passages, liver, and prostate.
Mercury has been well known as an environmental pollutant for several decades. As early as the 1950đs it was established that emissions of mercury to the environment could have serious effects on human health. These early studies demonstrated that fish and other wildlife from various ecosystems commonly attain mercury levels of toxicological concern when directly affected by mercury-containing emissions from human-related activities. Human health concerns arise when fish and wildlife from these ecosystems are consumed by humans.
A high degree of pesticides had contaminated water in drains in parts of Ludhiana, Amritsar, Jalandhar and Nawanshahr.
The study says that blood samples collected from people in the area showed that in 65% of the cases the DNA had mutated.
The chairman of the Water Pollution Control Board, Yogesh Goel said that the recommendations had to be "debated and discussed".
He felt that the "industry alone was not to blame, the overuse of pesticides was another reason. We have to ascertain reasons for it".
Apart from studying the quality of water close to major drains in which effluents were discharged, the study also looked at the health profile of people in settlements close to these drains.
The pollution control chief said the board would study the report and make its recommendations to the government.
He said the study had recommended constant monitoring of water supply and sewerage, involvement of village councils in the treatment and disposal of solid waste, and the need for industries to adopt new technology in extracting ground water.
The state has begun implementing a World Bank project to improve water supply and sanitation in the state, he claimed.