Comparison of atmospheric nitropolycyclic aromatic hydrocarbons in Vladivostok, Kanazawa and Toyama

Airborne particulates were collected simultaneously at Vladivostok, Kanazawa and Toyama. 1,3-, 1,6-, 1,8-Dinitropyrenes (DNPs), 1-, 2-, 4-nitropyrenes (NPs), 2-nitrofluorene and 6-nitrochrysene in the particulates were analyzed by HPLC with chemiluminescence detection. All compounds were detected not only in Kanazawa but also in Vladivostok and Toyama. Moreover, five unknown peaks which might be nitropolycyclic aromatic hydrocarbons were detected only in chromatograms of Vladivostok. The [DNPs]/[1-NP] ratios at all stations were near the value found in diesel-exhaust particulates, suggesting that one of the main contributors of these compounds was diesel-engine vehicles not only in Kanazawa and Toyama but also in Vladivostok.. However, the difference in traffic volume at two stations in Vladivostok did not have a significant effect on the concentrations of DNPs and NPs in contrast to two stations in Kanazawa. These results suggested sources other than diesel-engine vehicles also contributing to DNPs and NPs in Vladivostok. Seasonal variations similar to those in Kanazawa were observed in Vladivostok and Toyama. As in Kanazawa, the [2-NP]/[1-NP] ratio in Vladivostok was larger at the lighter traffic station than that at heavier traffic station. This suggested that, as in Kanazawa, 2-NP was formed in the atmosphere in Vladivostok.