N-nitrosamines and nitrosatable amines, potential precursors of N-nitramines, in children's pacifiers and baby-bottle nipples.

Sixteen types of children's pacifiers and baby-bottle nipples, bought in shops in Israel but produced both there and elsewhere in the world, were analyzed for their contents of N-nitrosamines, which have been shown to be potent carcinogens in animals, and of nitrosatable amines. Two methods were used: one, originating in the United States, involved dichloromethane extraction of total volatile N-nitrosamines from the nipples and pacifiers, and the other, from the Federal Republic of Germany, consisted of analysis of N-nitrosamines and their amine precursors that migrated into artificial saliva. N-Nitrosodibutylamine (NDBA). N-nitrosodiethylamine (NDEA), N-nitrosodimethylamine (NDMA). N-nitrosopiperidine (NPIP), and N-nitrosopyrrolidine (NPYR) were detected by the first method, at individual levels as high as 369 ppb. Using the second method, NDBA, NDEA, NDMA, and N-nitrosomorpholine (NMOR) were detected at concentrations up to 41 ppb, in addition to the three nitrosatable amines dibutylamine, diethylamine, and dimethylamine. Upon nitrosation in the artificial saliva, these amines produced not only the related N-nitrosamines but also relatively high levels of the corresponding N-nitramines (N-nitrodibutylamine, N-nitrodiethylamine, and N-nitrodimethylamine), probably formed by oxidation of the N-nitrosamines by peroxides used for vulcanization of elastomers. Thus, if N-nitramines are not measured in addition to N-nitrosamines after nitrosation, the second method may underestimate 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, also occur in the saliva of babies exposed to these products remains to be confirmed. Of the samples tested, 50% failed to meet both the U.S. and the FRG regulations. A larger percentage, 60%, would not conform to the new standard suggested in the United States, and more than 80% failed to comply with the even stricter Dutch standard.