Evaluation of a Compact Sampler Designed for the Simultaneous Collection of Atmospheric Polycyclic Aromatic Hydrocarbons in Size-fractionated Particulate Matter and the Gaseous Phase

Abstract

A compact sampler consisting of a three-stage cascade impactor and a holder for polyurethane form (PUF) plugs was designed for the simultaneous collection of atmospheric polycyclic aromatic hydrocarbons (PAHs) in fine particles and the gaseous phase. To evaluate its collection efficiency, air was passed through a quartz-fiber filter (QFF) spiked with 28 authentic PAHs and then through cleaned PUF plugs and backup filters for 24hr in the dark at a constant room temperature (20 or 35°C). PAHs retained on the QFF and those trapped within PUF plugs and backup filters were separately determined. We observed no obvious difference in recoveries between 20 and 35°C except for benzo[a]anthracene (BaA) and triphenylene+chrysene. Most of the PAHs with low molecular weight (166-202) vaporised from the QFF and were trapped in the PUF plugs and backup filters at recoveries of 42-108%, while those with high molecular weight (≥252) were largely retained on the QFF (recoveries of 75-114%). BaA and triphenylene+chrysene (molecular weight=228) were largely retained on the QFF at 20°C (recoveries of ≥84%), but at 35°C the recovery values decreased to levels similar to those trapped with PUF plugs and backup filters (recoveries of 40-56%). The proposed sampler was applied in an investigation of ambient PAHs at a roadside site in a heavy-traffic area in Osaka, Japan, during August 2006 and February 2007.