The concentrations of organophosphate flame retardants (OPFRs) in the indoor air and dust were measured in 25 unoccupied cars in Japan. In the indoor air of the cars, most OPFRs were neither detected nor found at a concentration lower than the method quantification limit. The highest concentration (1500 ng m-3) was obtained for tris(1-chloro-2-propyl) phosphate (TCIPP). By contrast, many OPFRs were detected in the dust samples collected from the interior of the cars. TCIPP and tris(2-ethylhexyl) phosphate (TEHP) were present at the highest concentrations at 390 μg g-1 (in dust from car seats) and 640 μg g-1 (in dust from car floor mats), respectively. The highest median concentrations (35 μg g-1 for car seats, 53 μg g-1 for car floor mats) were obtained for tris(2-butoxyethyl) phosphate (TBOEP). According to the results of our exposure assessment, the typical exposures to OPFRs via inhalation in car cabins ranged from 9.0×10-4 to 7.8×10-1 ng kg-bw-1 day-1. The typical exposures to OPFRs via dust ingestion ranged from 9.2×10-4 to 8.8×10-1 ng kg-bw-1 day-1. We compared these results with the ref-erence doses for OPFRs and found that, based on cur-rent information about the toxicities of OPFRs, exposure to OPFRs in car cabins via inhalation and dust ingestion is unlikely to have adverse human health effects.
Keywords: Air pollution; Car interior air quality; Dust ingestion; Exposure assessment; Flame retardants; Risk assessment.