2013 Environment and Health - Basel
Health Risks of Flame Retardants in California House Dust
Background: Higher house dust levels of polybrominated diphenyl ether (PBDE) flame retardants (FRs) have been reported in California (CA) than in other US states. Whereas PBDE exposures have been well-studied, little is known about exposures to and potential risks from other FRs. In a recent study in CA homes, we found 44 FRs, representing the broadest investigation of FRs in house dust to date. Our work suggests that manufacturers continue to use chemicals with health concerns and introduce chemicals with uncharacterized toxicity.
Aims: To provide perspective on potential health risks associated with exposures to FRs in CA homes, we compare dust concentrations to available risk-based screening levels. We also explore gaps in health information and highlight areas for further research.
Methods: We analyzed 2011 CA house dust samples for 49 FRs: PBDEs, Firemaster® 550, other brominated FRs, and halogenated and non-halogenated organophosphate FRs (OPFRs). We compared FR levels with EPA residential soil screening levels or screening levels derived using available cancer slope factors. Results: We detected 43 FRs. Risk-based screening levels are available for pentaBDEs, octaBDEs, hexabromobenzene, 2 chlorinated OPFRS, and 2 non-halogenated OPFRs. We derived screening levels for tris(1,3-dichloro-isopropyl)phosphate (TDCIPP) and tris(2,3-dibromopropyl)phosphate. Half of the homes had levels that exceeded at least one screening level. Levels of tris(2-chloroethyl)phosphate (TCEP) and TDCIPP, CA Proposition 65 carcinogens, and BDE 47 and BDE 99 exceeded screening levels. TCIPP levels were below a non-carcinogenic screening level; however, long-term carcinogenicity studies have not been conducted despite structural similarity to TDCIPP and TCEP. Screening levels were not available for other FRs, often because of a lack of toxicity studies.
Conclusions: The continued use of FRs with established health concerns and those with limited data highlights the need to modernize US chemical policies to require more thorough testing and disclosure of chemicals prior to sale.