Modification and Calibration of a Passive Air Sampler for Monitoring Vapor and Particulate Phase Brominated Flame Retardants in Indoor Air: Application to Car Interiors

A passive air sampler was modified to monitor both vapor and particulate phase brominated flame retardants (BFRs) in indoor air using polyurethane foam disks and glass fiber filters (GFF). Significant correlation (p <0.01) was observed between passive (ng day(-1)) and active sampler (ng m(-3)) derived BFR concentrations in an office microenvironment (r = 0.94 and 0.89 for vapor and particulate phase BFRs, respectively). A calibration experiment was performed where concentrations of target BFRs were obtained for an office using a low volume active sampler operated over a 50 day period alongside passive samplers. The passive uptake rates of each studied BFR ranged between (0.558-1.509 ng day(-1)) and (0.448-0.579 ng day(-1)) for vapor and particulate phases, respectively. The passive entrapment of particles by the GFF was investigated using environmental scanning electron microscopy which revealed gravitational deposition of particles as the main mechanism involved. The developed sampler was applied to monitor BFR concentrations in 21 cars. Average concentrations of Sigma HBCDs, TBBP-A, and Sigma tetra-deca BDEs were 400, 3, and 2200 pg m(-3) in cabins and 400, 1, and 1600 pg m(-3) in trunks. No significant differences (p <0.05) were observed between levels of Sigma HBCDs and Sigma trito hexa- BDEs in cabins and trunks. However, TBBP-A, BDE-209, and Sigma PBDEs concentrations were significantly higher in vehicle cabins.