Presence and human exposure assessment of organophosphate flame retardants (OPEs) in indoor dust and air in Beijing, China.

In this study, levels of 14 organophosphate flame retardants (OPEs) were measured in 101 indoor dust samples collected from dormitories, residential homes, and offices in Beijing, China. In addition, paired air samples were also analyzed to evaluate any correlation between OPE levels in air and that in corresponding dust samples. The Σ14OPEs levels substantially varied between individual samples. Thereinto, significantly higher OPE levels were found in dust samples from office (mean value: 14 μg g-1), comparing to that in dust samples from residential homes (mean value: 5.9 μg g-1) and dormitories (mean value: 6.9 μg g-1). Congener profiles of OPEs in dust samples from different microenvironments indicated that tris (2-chloroethyl) phosphate (TCEP) was the dominant OPE in the office samples, followed by tris (2-chloroisopropyl) phosphate (TCPP). In contrast, TCPP was the dominant OPE in the residential home and dormitory samples, followed by TCEP. The mean concentration (range) of Σ14OPEs in the 15 air samples was 5.2 (1.0-20) ng m-3, and TCPP was the dominated congener in these samples. The concentration of TCEP and TCPP in air was positively correlated with that in corresponding indoor dust, and OPEs with highly saturated vapor pressures have higher fractions in the air than that in the dust. The estimated daily intakes through dust ingestion, dermal absorption, and inhalation indicated that the exposure to OPEs in indoor environments do not result in significant health risk for the general population in Beijing.