The size distributions of ambient air metallic pollutants by using a multi-stage MOUDI sampler

Abstract

Particle concentrations of metallic elements in ambient air were determined using a micro-orifice uniform deposition impactor (MOUDI). Comparisons were also made of particle concentrations of various sizes (PM18+, PM18-10, PM10-2.5, and PM2.5-1) sampled at Westin Park and at Gung-Ming Junior High School (Taichung airport). Comparing the particle sizes of PM18+, PM18-10, and PM10-2.5 revealed higher concentrations in Westin Park than those in Gung-Ming Junior High School (Taichung airport). The only exception was PM2.5-1, indicating higher concentrations at the Gung-Ming site. The average particle concentrations order was Gung-Ming Junior High School (Taichung airport) > Westin Park for the particle size of PM2.5-1. According to analysis results of various particle sizes of metallic elements Zn, Ni, Cu, Cd and Pb in the ambient air, the relative concentrations were PM18+ > PM18-10 > PM2.5-1 > PM10-2.5 for all sampling sites. The only exception was particle-bound mercury Hg(p), likely owing to the proximity of the Taichung airport to the Taiwan Strait (approximately 11.6 km). Moreover, Dragon Steel Plant, Han-Shian Aerospace Industrial Development Corporation and Quan-Lien Industrial Park were located nearby. © Taiwan Association for Aerosol Research.