bilharzia patients prior to , and after , diagnosed bladder cancer regularly excreted free nitrite as well as volatile nitrosamines ( n-nitrosodimethylamine , n-nitrosodiethylamine , n-nitrosopiperidine and n-nitrosopyrrolidine ) in addition to which elevated concentrations of non-volatile n-nitrosamino acids ( n-nitrosoproline , n-nitrososarcosine , n-nitrosothiazolidine-4-carboxylic acid and its 2-methyl derivative ) were also present .
C0028197
nitrosamines
C0012431
n-nitrosodimethylamine