Polydimethylsiloxane (silicone rubber) brooch as a personal passive air sampler for semi-volatile organic compounds

Exposure assessments conducted using a personal sampler include the contribution of human activities to exposure that is neglected when using a stationary air sampler. This study evaluated the uptake characteristics and application of the polydimethylsiloxane (PDMS or silicone rubber) brooch as a personal passive air sampler (PPAS) for measuring concentrations of two groups of semi-volatile organic compounds (SVOCs), namely phthalates and organophosphate esters (OPEs), indoors in proximity to the breathing zone. Uptake rates of the PDMS brooch were calibrated against a personal low volume active air sampler (PLV-AAS) co-deployed on each of five study participants working in offices for 8 hs daily for four days. Sampling rates measured here ranged from 0.41 ± 0.33 to 1.33 ± 0.34 m³ day^-1 dm^-2 with an average value of 0.86 ± 0.29 m³ day^-1 dm^-2. Personal air concentrations of 1211 to 2640 ng m^-3 for ∑₅ phthalates and 254 to 663 ng m^-3 for ∑₅ OPEs were measured for three study participants who used the PDMS brooches continuously for seven days. These concentrations resulted in estimated inhalation exposures of 19,400 to 42,400 ng day^-1 for ∑₅ phthalates and 4,070 to 10,600 ng day^-1 for ∑₅ OPEs. This study demonstrated that the PDMS brooch can be used to assess inhalation exposure when worn for at least 24 h indoors, for compounds present in >4 ng m^-3 in air such as individual phthalates and OPEs tested here.