Possible underestimation of nitrosatable amine levels in artificial saliva extracts of children's rubber pacifiers and baby-bottle teats.

Children's pacifiers and baby-bottle nipples from various countries were analysed for their content of N-nitrosamines and nitrosatable amines. Using a method involving extraction with artificial saliva, several nitrosamines including N-nitrosodi-n-butylamine (NDBA), N-nitrosodiethylamine (NDEA), N-nitrosodimethylamine (NDMA) and N-nitrosomorpholine (NMOR) were detected in addition to the three nitrosatable amines dibutylamine (DBA), diethylamine (DEA) and dimethylamine (DMA). Upon nitrosation in artificial saliva, these amines produced not only the related N-nitrosamines but also relatively high levels of the corresponding nitramines--N-nitrodibutylamine (NTDBA), N-nitrodiethylamine (NTDEA) and N-nitrodimethylamine (NTDMA). Thus, both N-nitramines and N-nitrosamines should be measured after nitrosation; otherwise, the method probably underestimates the quantities of nitrosatable amines present in artificial saliva extracts. Whether N-nitramines, some of which have been shown to be both mutagenic and carcinogenic, are formed in the saliva of babies exposed to these products remains to be confirmed.