Formation of carcinogenic nitrosamines in soils

Abstract

The possible formation of carcinogenic nitrosamines in soils was examined. Soil samples amended with NO 2 −-N and dimethylamine incubated for 30 days and analysed every 3 days, showed increasing amounts of dimethylnitrosamine up to 12–15 days. The concentration reached as high as 6.5 parts/10 6, thereafter, a decline was noted. Most of the nitrosamines disappeared in soils after 30 days. Addition of inorganic N reduced the decomposition of dimethylamine. Soil incubation studies with NO 2 − and trimethylamine showed about 80% reduction in the amount of nitrosamines formed as compared to dimethylamine. Analysis of soil samples from fertilized and polluted areas showed significant amounts of NO − 3-N but no nitrosamines. Application of 10 parts/10 6 of dimethylamine to these soil samples resulted in the formation of 0.10 to 0.50 parts/10 6 of nitrosamines. Autoclaved soil samples incubated with NO 2 − and dimethylamine for 12–15 days produced small amounts of nitrosamines. Addition of glucose to soil samples increased the amounts of nitrosamines formed.