N‐nitrosamines and mutagens in rubber nursing nipples

Aqueous extracts of four brands (eight types) of rubber nursing nipples purchased in the open market were analyzed for volatile N‐nitrosamines, diphenylamine, and mutagenic activity. N‐Nitrosodimethylamine, N‐nitrosodiethylamine, or N‐nitro‐sopiperidine were found in the aqueous extracts of the nipples and in the nipples themselves. All nipples analyzed contained one or more of the three volatile N‐nitrosamines. Diphenylamine was found to be continously released into aqueous extracts from most brands. Certain nipples produced a positive mutagenic response when incubated with Salmonella typhimurium (TA 100) in a modified liquid suspension test.