Determination of the levels of aromatic amines in indoor and outdoor air in Italy.

We studied the concentration of 10 primary aromatic amines (AA), which are classified as suspected carcinogens, in indoor and outdoor air in Italy. The measured AA included: aniline, o-toluidine, m-toluidine, p-toluidine, 2,3-dimethylaniline, 2,4-dimethylaniline, 2,5-dimethylaniline, 2,6-dimethylaniline, 2-naphtylamine and 4-aminobiphenyl. In the indoor environment (homes, offices and public buildings) the level of contamination (expressed as sum of 9 AA, excluding aniline) varied from 3 ng/m3 (hospital ward) to 207 ng/m3 (discotheque). In most indoor environments with no contamination from cigarette smoke the AA levels were below 20 ng/m3, whereas in the presence of smokers higher values were observed. Aniline levels were more erratic (varying from 53 ng/m3 (office of non-smokers) to 1929 ng/m3 (discotheque) and were not related to cigarette smoke. The concentration range of AA (excluding aniline) in the outside air varied from 3 ng/m3 (Siena) to 104 ng/m3 (Brindisi); aniline concentration was extremely variable. Most samples of outdoor air had AA levels lower than 40 ng/m3. In conclusion, AA are widespread air contaminants and attain a high concentration in heavily contaminated indoor environments, due to smoking and poor ventilation. AA occasionally attain a high level in outdoor air as well. Therefore, a strategy of reduction of the exposure to AA should consider the abatement of multiple sources of contamination.