Field calibration of low density polyethylene passive samplers for gaseous POPs

Abstract

A field calibration study of low density polyethylene (LDPE) for measuring atmospheric concentrations of persistent organic pollutants (POPs) was performed in East Providence (RI), USA. LDPE samplers were collected after 3, 7, 10, 14, 17 and 21 days of exposure along with samples from a co-deployed high volume sampler. Uptake kinetics of POPs by LDPEs were confirmed both by using an uptake study over time and the inclusion of performance reference compounds (PRCs). Results indicated that only POPs with log sampler–air partitioning coefficient (K_PE-A) ≤ 7.6 were approaching equilibrium by the end of the deployment period, whereas all the other POPs were still in the linear uptake rate. Sampling rates (1.0–80 m³ per day) were higher for some POPs when compared to literature values possibly due to the open sampler housing design used. Derived K_PE-As for the detected POPs in field calibration study were correlated against the compounds' octanol–air partitioning coefficients (log K_OA): [log K_PE-A = 0.88 ± 0.02 × log K_OA + 0.40 ± 0.21 (R² = 0.96; n = 59; SE = 0.23)], and their subcooled liquid vapour pressures (log P_L/P_a): [log K_PE-A = −0.82 ± 0.02 × log P_L + 6.22 ± 0.05 (R² = 0.96; n = 59; SE = 0.22)] to predict values for all POPs. P_L was generally found to be a better predictor of K_PE-A for all POPs.