抄録
In the summers of 2003 and 2004, size-separated suspended particulate matter (SPM) samples were collected with a high-volume Andersen air sampler at a site adjacent to Saitama Prefectural Route 57 in Saitama City. This sampling site is in an atmospherically polluted area that is also one of the “Specified Areas concerning Special Measures for Total Emission Reduction of Nitrogen Oxides and Particulate Matter from Automobiles” established in October 2002. We investigated carbonaceous compounds in the SPM before and after the Regulation on Diesel Vehicle Exhaust came into effect in October 2003 in Tokyo Metropolis and Saitama, Chiba, and Kanagawa prefectures. At the sampling site, elemental carbon (EC) in the fine particles (< 2µm) was derived mainly from diesel vehicle exhaust emissions, and crustal metals such as Al, Fe, and Mg in the coarse particles (> 2µm) were generated as road dust by vehicular traffic and wind. Correlations among chemical components generated by heavy-duty diesel vehicles suggest that the air quality is improving at the sampling site as a result of the enforcement of the Regulations on Diesel Vehicle Exhaust.
