A Prototype Passive Air Sampler for Measuring Dry Deposition of Polycyclic Aromatic Hydrocarbons

Anita Eng,Tom Harner,Karla Pozo

doi:10.1021/ez400044z

Abstract

The passive dry deposition (Pas-DD) collector is presented as a tool for estimating atmospheric loadings (dry deposition fluxes or maps) for polycyclic aromatic hydrocarbons (PAHs) and other semivolatile compounds. Pas-DD collectors based on a parallel plate design were codeployed with conventional polyurethane foam (PUF) disk passive air samplers (PAS) in outdoor urban air over different seasons. Two configurations of sampling media (PUF only vs stacked glass fiber filter on PUF) were used. For both samplers, a higher level of accumulation of PAHs was observed when only the PUF disk was used as the sampling medium. The Pas-DD collector and the PAS accumulated gas-phase PAHs (dry gaseous deposition component) to a similar extent. For the higher-molecular weight PAHs that are associated with particles, the Pas-DD collector was enriched relative to the PAS. Dry deposition velocities derived from the Pas-DD collector were approximately 0.16 cm/s for gas-phase PAHs and up to 0.8 cm/s for particle-phase PAHs.

Highlights

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous atmospheric pollutants that are a concern because of their toxicity
The passive dry deposition (Pas-DD) collector is presented as a tool for estimating atmospheric loadings for polycyclic aromatic hydrocarbons (PAHs) and other semivolatile compounds
For the higher-molecular weight PAHs that are associated with particles, the Pas-DD collector was enriched relative to the passive air samplers (PAS)

Summary

INTRODUCTION

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous atmospheric pollutants that are a concern because of their toxicity. This time-integrated sampler is well suited for deployment in remote sites over large regions, where sampling using conventional air sampling equipment is logistically challenging because of the nature of the environment and the lack of access to electricity and infrastructure Such a need exists in the Athabasca oil sands region, where there are concerns associated with deposition of PAHs to terrestrial and aquatic environments and the associated health risks.[6,11] The use of the Pas-DD collector to collect PAH dry deposition data at a high spatial resolution to generate deposition maps is analogous to the way that mosses, lichens, and other biomonitors are used to map spatial deposition, but overcoming some of the inconsistency and interpretation challenges associated with biomonitoring.

METHODS

RESULTS AND DISCUSSION

■ ACKNOWLEDGMENTS

■ REFERENCES