Ambient air pollution by particle associated PAH in the Greater Wellington Region of New Zealand

Abstract

The concentrations of seventeen particle (PM10) associated polycyclic aromatic hydrocarbons PAHs (naphthalene, acenaphthylene, acenaphthene, fluorene, anthracene, phenanthrene, fluoranthene, pyrene, benzo[a]anthracene, chrysene, retene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene,benzo[ghi]perylene, indeno[l,2,3-cd]pyrene and dibenzo[a,h]anthracene) were measured at Masterton and Wainuiomata, in the Greater Wellington Region. The average total PAH concentrations in PM10 were 5.69 ng m-3 in Masterton and 8.50 ng m-3 in Wainuiomata during the sampling periods. The relationships between PM10 and its associated total PAH concentrations were investigated. It was concluded that using PAHs as fingerprint compounds to identify the pollution sources of PM10 may be appropriate in winter but not in summer. The meteorological effects on PAH concentrations were also investigated in this study. Distinct seasonal variations of PAH concentrations were observed at both the sampling sites with much higher PAH concentrations in winter. Based on the diagnostic ratios between PAHs and Principal Component Analysis (PCA) approaches, wood combustion was identified as the main contributor for winter air pollution in both Masterton and Wainuiomata. Annual average benzo[a]pyrene concentration exceeded the National Environment guideline value (0.3 ng m-3) in both towns and the health hazard of human PAH exposure was more severe in winter than in summer.