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AIM To understand the pollution status of drinking water in Cixian area and to find out a way to solute it.METHODS Contents of nitrate nitrogen, nitrite nitrogen and ammonia nitrogen were measured andcompared with controls and national standards.RESULTS Levels of nitrate nitrogen, nitrite nitrogen and ammonia nitrogen were higher than the nationalpermissive levels by 20.60%, 50.50% and 33.30% respectively. Also the levels in Cixian are significantlyhigher than those of a controls areas of Chicheng - a county with very low incidence rate of esophagealcancer.CONCLUSION Three nitrogen levels in drinking water correlate both with the amount of N-containingfertilizer used in these areas and the mortality rates of esophageal cancer.