Field Calibration of Rapidly Equilibrating Thin-Film Passive Air Samplers and Their Potential Application for Low-Volume Air Sampling Studies

摘要

This paper reports on a field calibration and ambient deployment study with rapidly equilibrating thin-film passive air samplers. POIymer-coated Glass (POG) samplers have a coating of ethylene vinyl acetate (EVA) less than 1 μm thick coated on to glass, which can be dissolved off after exposure and prepared for quantification of persistent organic pollutants (POPs) that have partitioned into the film during field exposure. In this study, POGs were exposed for up to 18 d, in a study to assess compound uptake rates and their time to approach equilibrium. Results confirmed theoretical predictions, with time to equilibrium varying between a few hours to ca. 20 d for PCB-18 and PCB-138, respectively. Performance reference compounds and contaminated POGs were used to investigate depuration kinetics, confirming that lighter congeners behave extremely dynamically with substantial losses from the films over periods of a few hours. Repeated deployments of the samplers for different 3-d periods yielded detectable levels of a range of PCB congeners, which had partitioned from as little as ～2 to 10 m{sup}3 air. This highlights the potential utility of POGs for extremely sensitive and dynamic passive air sampling in the future to help improve understanding of sources, environmental fate, and behavior of POPs. Recommendations are made for future improvements/refinements in POG sampling and handling procedures.