Exposure to Organophosphate Esters and Brominated Flame Retardants: What Does Your Cell Phone Tell You?

Abstract

BackgroundWidespread exposure to organophosphate esters (OPEs), used as flame retardants and plasticizers, is of concern due to emerging data on toxicity. We aimed to identify OPE concentrations and pathways of exposure to Canadian pre-menopausal women, and to compare that with brominated flame retardants (BFRs).MethodsFrom 51 women in Toronto and Ottawa, we measured concentrations of OPEs in air and floor dust in their homes, and on their hands and their electronic devices. 557 samples were analyzed for 23 OPEs, 9 “novel” brominated flame retardants and 14 PBDE congeners. Also, urine samples from 44 participants were analyzed for 8 OPE metabolites.Results and DiscussionOPE air and dust concentrations were in the low ng/m3 and µg/g ranges, respectively, for 5-8 OPEs with >80% detection frequency. BFRs were ~100X lower. Eight OPEs also had >80% detection frequency on hands (up to µg/cm2 levels) that were similar in samples taken 3 weeks apart. Handheld electronic devices (e.g., cell phone, tablet) had significantly higher OPE (but not BFR) concentrations than non-handheld devices (e.g., TV, desk top). OPE concentrations on hands were most frequently correlated with those on cell phones, whereas BFRs on hands were correlated with laptops. Moreover, we found a significant correlation between total ∑OPE concentrations on cell phones and those in the corresponding urine sample, driven mostly by Triphenyl Phosphate (TPhP). We also found a significant correlation between the parent compound TDCPP in dust and cell phones and the corresponding urinary metabolite. Only TCPP on hands was correlated with its urinary metabolite.ConclusionsOur study confirmed widespread exposure to OPEs among Canadian women. We found that OPE exposure could in part be explained by levels found on a woman’s cell phone and secondarily by concentrations in her residential floor dust and her hands. It is not clear whether the cell phones are acting as a source or indicator of exposure to OPEs.