大気中の芳香族ニトロ化合物に関する研究(第3報)大気浮遊粉じんおよび自動車排出物中の1-ニトロピレンの定量

抄録

The concentrations of 1-nitropyrene and polynuclear aromatic hydrocarbons were measured in a variety of air borne and source particulate samples. Airborne and automobile exhaust particulates were collected on glass fiber filters by high volume air sampler. Organic compounds in the samples were extracted with benzene-methanol (4 : 1, v/v) using Soxhlet apparatus. The compounds extracted were separated into neutral, acidic and basic fractions. The neutral fraction was chromatographed on a silica gel column and divided into four portions. Pyrene, fluoranthene and benzo (a) pyrene were contained in the secound fraction which was eluted with hexane-benzene (1 : 1, v/v), were determined by high performance liquid chromatography. 1-Nitropyrene was contained in the third fraction which was eluted with benzene and then, was converted to 1-aminopyrene by the reduction with hydrochloric acid and zinc powder. 1-Aminopyrene extracted with benzene was converted to the acyl derivative with heptafluorobutyric anhydride. 1-Aminopyrene-heptafluorobutyric derivative was determined by means of gas chromatograph equipped with a ⁶³Ni electron capture detector and gas chromatography-mass spectrometry. Airborne particulate matter collected at the industrial area and in a tunnel contained 1-nitro-pyrene of 0.24-0.48μg/g (21.5-71.6pg/m³) and 0.35-0.96μg/g (0.94-5.65ng/m³), respectively. 1-Nitropyrene detected from the catalyst car was accounted for 0.8μg/g, and that from diesel car 4.9-28.1μg/g in particulate. Two isomers of nitropyrene were detected from the airborne particulate matter, one of which was 4-nitropyrene, and the other was 2-nitropyrene or nitrofluoranthene.