Detection of monocyclic aromatic amines, possible mammary carcinogens, in human milk

Environmental chemicals may play a role in the etiology of human breast cancer. Aromatic amines, industrial chemicals found as environmental pollutants, have been Identified as rat mammary carcinogens. We have detected the monocyclic aromatic amines, aniline, o-toluidine, and N-methylaniline at parts per billion levels in human milk samples, by applying solid-phase microextraction coupled with gas chromatography/mass spectrometry. Our findings indicate that human breast ductal epithelial cells are directly exposed to aromatic amines, including o-toluidine, which is a mammary carcinogen in female rats.