Design and validation of portable SPME devices for rapid field air sampling and diffusion based calibration

The use of SPME fibers coated with porous polymer solid phases for quantita tive purposes is limited due to effects such as interanalyte displacement a nd competitive adsorption. For air analysis, these problems can be averted by employing short exposure times to air samples flowing around the fiber. In these conditions, a simple mathematical model allows quantification with out the need of calibration curves. This work describes two portable dynami c air sampling (PDAS) devices designed for application of this approach to nonequilibrium SPME sampling and determination of airborne volatile organic compounds (VOCs). The use of a PDAS device resulted in greater adsorbed VO C mass compared to the conventional SPME extraction in static air for quali tative screening of live plant aromas and contaminants in indoor air. For a ll studied air samples, an increase in the number of detected compounds and sensitivity was also observed. Quantification of aromatic VOCs in indoor a ir was also carried out using this approach and the PDAS/SPME device. Measu red VOC concentrations were in lour parts-per-billion by volume range using only 30-s SPME fiber exposure and were comparable to those obtained with a standard NIOSH method 1501. The use of PDAS/SPME devices reduced the total air sampling and analysis time by several orders of magnitude compared to the NIOSH 1501 method.