Computer-Controlled Low-Volume Air Sampler for the Measurement of Semivolatile Organic Compounds

Abstract

We have developed an automated, low-volume air sampler, capable of collecting multiple samples for semivolatile organic compound analysis in a short time (several hours). The new sampler uses small polyurethane foam plugs as the sampling media and a sampling carousel that has a 20 plug capacity. A computer controls the sampling protocol, and after the sampler is loaded with plugs, a sampling program is carried out with no operator intervention. The plugs are removed, and the analyte is extracted by supercritical fluid extraction. A series of quality control experiments were undertaken to demonstrate thatthe new sampler performed properly. Air volumes in the range of 100 m 3 can be collected without exceeding the breakthrough volume of the foam plugs. Passive sampling and volatilization artifacts are minimal. Concurrent air measurements using our new sampler and a conventional high-volume air sampler over a week-long period gave statistically identical (at the 95% significance level) air concentrations for polychlorinated biphenyls and endosulfan.