Groups of 15 male and 15 female MRC rats were given 0.5% nitrilotriacetic acid (NTA) or 0.5% iminodiacetic acid (IDA) in drinking water, with and without 0.2% sodium nitrite (NaNO2) or 0.5% sodium nitrate (NaNO3) for most of their lifespans. The dose was 20 ml solution per animal 5 days a week. The expected in vivo nitrosation product, nitrosoiminodiacetic acid (NIDA) was administered similarly at 0.2% in drinking water. The total dose received by each animal was 42 g NTA, IDA, or NaNO3, 16 g NaNO2, or 14.4 g NIDA. No significant difference in tumor induction was noted between the treated groups or between them and the untreated controls.