Personal exposure to HBCDs and its degradation products via ingestion of indoor dust.
Personal exposures via ingestion of indoor dust to alpha-, beta-, and gamma-hexabromocyclododecanes (HBCDs) and the degradation products (pentabromocyclododecenes (PBCDs) and tetrabromocyclododecadienes (TBCDs)) were estimated for 21 UK adults. Under an average dust ingestion scenario, personal exposures ranged from 4.5 to 1851 ng SigmaHBCDs day(-1); while the range under a high dust ingestion scenario was 11 to 4630 ng SigmaHBCDs day(-1). On average, personal exposure to SigmaHBCDs via dust ingestion in this study was 35% alpha-, 11% beta-, and 54% gamma-HBCD. However, while exposure to beta-HBCD (4-18% of SigmaHBCDs) was relatively consistent with the proportion of this diastereomer in the HBCD commercial formulation; exposures to alpha- and gamma-isomers (11-58% and 29-82% of SigmaHBCDs respectively) showed substantial variation from the commercial formulation pattern. Personal exposures to SigmaTBCDs (median=0.2 ng day(-1) under an average dust ingestion scenario) and SigmaPBCDs (1.4 ng day(-1)) were significantly lower (p<0.05) than for SigmaHBCDs (48 ng day(-1)). Despite this, the exposure of one participant to SigmaPBCDs exceeded the exposure to SigmaHBCDs received by 85% of the other participants. On average, house dust provided the major contribution to personal exposure via dust ingestion to all target compounds due to the large time fraction spent in houses. In contrast, although participants spent less time in cars than in offices, car dust makes a higher average contribution (17%) to SigmaHBCDs exposure than office dust (13%).
Division of Environmental Health and Risk Management, School of Geography, Earth and Environmental Sciences, University of Birmingham, Birmingham, B15 2TT, United Kingdom. maa684@bham.ac.uk
Mohamed Abou-Elwafa
MA
Abdallah
Stuart
S
Harrad
D000328:Adult; D016902:Air Pollution, Indoor / Q000032:analysis*; D001336:Automobiles; D004391:Dust / Q000032:analysis*; D004435:Eating; D004781:Environmental Exposure; D004784:Environmental Monitoring; D005411:Flame Retardants / Q000032:analysis*; D006798:Housing; D006801:Humans; D006842:Hydrocarbons, Brominated / Q000032:analysis* / Q000737:chemistry; D019570:Inhalation Exposure / Q000032:analysis*; D007536:Isomerism; D017132:Workplace
D004391:Dust; D005411:Flame Retardants; D006842:Hydrocarbons, Brominated; C521198:pentabromocyclododecene; C089796:hexabromocyclododecane