Detection and intake assessment of organophosphate flame retardants in house dust in Japanese dwellings

Organophosphate flame retardants and plasticizers in the air and dust in German daycare centers and human biomonitoring in visiting children (LUPE 3)

Organophosphate (OP) flame retardants and plasticizers are chemicals that have been used in large quantities in diverse consumer and building-related products for decades. In the present study, OPs were measured in paired indoor air and dust samples from 63 daycare centers in Germany. Moreover, the urine of 312 children between 22 and 80 months old who attend these facilities was analyzed for the presence of eight OP metabolites. Tri-(2-butoxyethyl)-phosphate (TBEP), tris-(2-chloroisopropyl) phosphate (TCPP), and tri-n-butyl-phosphate (TnBP) were present in low concentrations in indoor air, with median values of 49 ng/m(3), 2.7 ng/m(3), and 2.2 ng/m(3), respectively. In dust, median values of 225 mg/kg for TBEP, 2.7 mg/kg for TCPP, 1.1mg/kg for diphenyl(2-ethylhexyl) phosphate, and 0.5mg/kg for tri-phenyl-phosphate (TPhP) were found. In the urine samples, the metabolites di-phenyl-phosphate, di-n-butyl-phosphate, and di-(2-butoxyethyl)-phosphate had median values (95th percentiles) of 0.8 μg/l (4.0 μg/l), 0.2 μg/l (0.9 μg/l), and 2.0 μg/l (10.7 μg/l), respectively. A significant correlation was found between the dust and air samples in the levels of TnBP, tris(2-chloroethyl) phosphate (TCEP), and TBEP. For TCEP and TBEP, significant correlations were also observed between the levels in dust and the respective metabolite levels in urine. For TCEP, there was also a significant correlation between the concentration in indoor air and metabolite levels in urine. Based on the 95th percentile in dust and air in our study and data from residences in a previously published study, the daily intake of the most abundant OP (TBEP) is high (i.e., 3.2 μg/kg b.w.). This level is approximately 6.4% of the reference dose (RfD) established by the NSF, U.S.A. Overall, our study shows that daycare centers are indoor environments that contribute to OP exposure.

Pilot-scale incineration of wastes with high content of chlorinated and non-halogenated organophosphorus flame retardants used as alternatives for PBDEs

Chlorinated and non-halogenated organophosphorus flame retardants (OPFRs) including tris(2-chloroisopropyl) phosphate (TCIPP), diethylene glycol bis(di(2-chloroisopropyl) phosphate) (DEG-BDCIPP), triphenyl phosphate (TPHP), and bisphenol A bis(diphenyl phosphate) (BPA-BDPP) have been used increasingly as alternatives to polybrominated diphenyl ethers and other brominated flame retardants. For this study, five batches of incineration experiments of wastes containing approximately 1% of TCIPP, DEG-BDCIPP, TPHP, and BPA-BDPP were conducted using a pilot-scale incinerator. Destruction and emission behaviors of OPFRs were investigated along with the effects on behaviors of unintentional persistent organic pollutants (POPs) such as polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), dioxin-like polychlorinated biphenyls (dl-PCBs), hexachlorobenzene (HCB), pentachlorobenzene (PeCB), and pentachlorophenol (PCP). Incineration conditions were chosen according to current regulations for waste incinerators in Japan and UNEP. The OPFRs in the input materials were mainly destroyed in the primary combustion with destruction efficiencies greater than 99.999%. Concentrations of the OPFRs in the exhaust gases and ash were, respectively, <0.01-0.048 μg m(-3) and <0.5-68 μg kg(-1). Almost all of the total phosphorus in the input materials was partitioned into the ash, but less into final exit gases, indicating negligible emissions of volatile phosphorus compounds during incineration. Inputs of chlorinated OPFRs did not affect the formation markedly. Destruction and emission behaviors of unintentional POPs were investigated. Emissions of such POPs in exhaust gases and the ash were lower than the Japanese and international standards. Results show that even in wastes with high contents of chlorinated and non-halogenated OPFRs, waste incineration by the current regulations for the waste incinerators can control environmental emissions of OPFRs and unintentional POPs. Incineration is regarded as a best available technology (BAT) for waste management systems.