Evaluation of a passive sampler for volatile organic compounds at ppb concentrations, varying temperatures, and humidities with 24-h exposures. 2. Sampler performance

The performance of the 3M 3520 organic vapor monitor (OVM) as a tool for mo nitoring inhalation exposures to volatile organic compounds (VOCs) in nonoc cupational community environments was evaluated by using combined controlle d test atmospheres of benzene, 1,3-butadiene, carbon tetrachloride, chlorof orm, 1,4-dichlorobenzene, methylene chloride, styrene, tetrachloroethylene, and toluene. Eight OVMs were simultaneously exposed to concentrations of 1 0, 20, and 200 mu g/m(3) in combination with temperatures of 10, 25, and 40 degrees C and relative humidities of 12, 50, and 90% for 24 h. The results of this study indicate that the performance of the 3520 OVM is compound-sp ecific and depends on concentration, temperature, and humidity. With the ex ception of 1,3-butadiene under most conditions and styrene and methylene ch loride at very high relative humidities, recoveries showed a negative bias as compared to calculated chamber concentrations but were generally within +/-25% of theory, indicating that the 3520 OVM can be effectively used over the range of concentrations and environmental conditions tested with a 24- h sampling period. Increasing humidities resulted in increasing negative bi as from full recovery. Reverse diffusion experiments conducted at 200 mu g/ m(3) and five temperature/humidity combinations indicated diffusion losses only for 1,3-butadiene, methylene chloride, and styrene under increased hum idity conditions. The recovery rates reported in this study can be used for estimating measurement biases when using OVMs for indoor, outdoor, and per sonal air monitoring of VOCs in community environments.