NITRATE CONTAMINATION OF DRINKING-WATER - AN EVALUATION OF HEALTH RISKS

Nitrate ground water contamination is a relatively frequent problem du e to the massive use of fertilizers in agriculture. The health effects of contamination are due to the transformation of nitrates into nitri tes in the G.I. tract and possibly the transformation of nitrites into nitrosamines in the stomach. The risk of methemoglobinemia in infants is due to nitrites contained in the water used to reconstitute milk f or feeding. There are possible but unproven risks associated with the formation of nitrosamines, i.e. teratogenous and cancer risks. Drinkin g water standards are only based on the risk of methemogloginemia, but given the present state of knowledge they appear to be safer in relat ion to the other potential risks. In the face of the increase in nitra tes in ground water and the partially known risks, it appears necessar y to try and prevent this type of contamination and inform the persons at risk, such as pregnant women and young mothers. It would also be u seful to promote research on the effects of nitrates and nitrites on h umans.