Trace elements in particles of motor vehicle exhaust in Shanghai

摘要

A nuclear microprobe with high spatial resolution and high analyticalsensitivity was applied to analyze trace elements, especially lead, in vehicle exhaust ofShanghai city. The result shows that the chemical composition and its correspondingx-ray relative intensity are different among different vehicle exhausts. There arc manykinds of metal elements in particles of vehicle exhaust, most are harnful to people,such as Ti, Cr, Mn, Pb, etc. We found that the lead concentration was 6820μg/g andthe bromine concentration was 5300 μg/g in the exhaust from Santana using leadedgasoline (SULG), which is higher than any other kinds of vehicle exhausts. We havealso detected the minimum lead in the particles of unleaded gasoline and its contentvaries from one to another. Its mean concentration was 450 μg/g and the highestreached 6210 μg/g. The unleaded gasoline's Pb existed in the whole particle while theleaded gasoline's enriched in the surface of the particle and was more harmful to thehuman beings.