Are We Exposed to Halogenated Flame Retardants from both Primary and Secondary Sources?

Abstract

Halogenated flame retardants (HFRs) were measured in air, floor dust, and surface wipes of electronic devices (e-devices) and hands of participants in 51 Canadian homes to assess the relationship between HFR levels in these matrices and to identify major sources and exposure pathways. Hand-held e-devices had significantly higher concentrations of all HFRs than non-hand-held devices, with the exceptions being decabromodiphenyl ethane (DBDPE) and decabromodiphenyl ether (BDE-209). HFR concentrations on hands were correlated with levels in dust and hand-held e-devices, with the strongest correlations being seen for BDE-47 and -99, 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (EH-TBB), and bis(3-ethylhexyl) tetrabromophthalate (BEH-TEBP). It is highly unlikely that hand-held devices sampled in 2015 had intentionally added BDE-47 and -99 that were regulated in 2008 in Canada. We hypothesize that hands transferred these chemicals from older products, which act as primary sources, to hand-held devices, which then can act as secondary sources of exposure. This study also found evidence for TVs as a primary source of DBDPE and BDE-209 for dust, hand-held devices, and hands. We suggest that an outdated, overly stringent flammability standard, developed in the 1970s to protect against fires from "instant-on" cathode ray tube TVs, led to elevated levels of these HFRs indoors. Although the standard for TV enclosures has been updated recently, the legacy of the outdated standard persists.

Hands as Agents of Chemical Transport in the Indoor Environment

“…Dust and surface wipes of most hand-held and non-hand-held electronic devices had high detection frequencies of most SVOCs analyzed (Figure S1). 13,39,46 This finding was contrary to our expectation that surface wipes of electronic devices would reveal one or very few dominant plasticizer(s) and/or flame retardant(s) that had been intentionally added to that product. the surface wipes of TVs that had increased concentrations of DBDPE and BDE-209 that, we believe, were intentionally added at high concentrations to those casings.…”

“…the surface wipes of TVs that had increased concentrations of DBDPE and BDE-209 that, we believe, were intentionally added at high concentrations to those casings. 46 We also found significantly higher concentrations of plasticizers and flame retardants in hand-held than non-hand-held devices, with the exceptions of DBDPE and BDE-209. We postulated that the discovery of multiple plasticizers and flame retardants in the surface wipes of all electronic devices was due to within-home partitioning of these SVOCs emitted from primary sources (e.g., TV casings, wiring, and upholstered furniture) to indoor surfaces that included other electronic devices.…”

“…This hypothesis was supported by significant correlations between chemical profiles on hands and hand-held devices. 13,39,46 We also found that chemical profiles from wipes of hand backs and palms were significantly correlated, although concentrations were higher on palms and concentrations were consistent in samples taken 3 weeks apart. 13,39,46 Similarity of Chemical Profiles.…”

“…We explored this hypothesis using a data set of SVOCs in residential air and dust and surface wipes of electronic devices and hands of 51 participants obtained through the OEHS-Homes Study (Ontario Environmental Health-Homes Study). The following SVOCs were measured: six phthalate esters, 13 22 halogenated flame retardants (HFRs), including 14 congeners of polybrominated diphenyl ethers (PBDEs), 46 and 23 organophosphate esters (OPEs). 39 This paper is the fifth in a series published from the OEHS-Homes Study; all data along with detailed explorations of associations and explanations have been previously published as noted above.…”

“…■ MATERIALS AND METHODS Chemical Concentration Data. Full details of the study design, sampling, and chemical analysis used in this analysis have been provided by Okeme and Yang et al, 47 Yang and Jı ́lkováet al, 13,39 and Yang et al 46 These publications also include detailed information about household characteristics such as the air exchange rate, house volume, activities, and information provided in questionnaires by participants where such factors were significantly related to chemical concentrations and profiles. Briefly, 51 women were recruited from the Toronto and Ottawa areas in Canada, aged 18−44 and of mid-socio-economic status.…”