Measurement of Polybrominated Diphenyl Ethers on Hand Wipes: Estimating Exposure from Hand-to-Mouth Contact

Abstract

Estimates of exposure to the flame-retardant polybrominated diphenyl ethers (PBDEs) in dust are very poor due to limited knowledge about dust ingestion. This study was undertaken to determine if PBDEs could be measured on hand wipes, and if so, to determine the distribution of levels present on the skin surface area to provide preliminary exposure estimates from hand-to-mouth contact. Hand wipes were collected from 33 individuals residing in the United States using sterile gauze pads soaked in isopropyl alcohol. The total PBDE residue collected on the wipes ranged from 2.60 to 1982 ng, with a median value of 130 ng, or normalized to hand surface area, a concentration of 135 pg/cm2. The fully brominated congener, BDE 209, was also detected and ranged from < DL to 270 ng with a median value of 26 ng. Congener patterns observed on the wipes were similar to patterns observed in house dust samples, consisting of congeners associated with the PentaBDE and DecaBDE mixtures, suggesting that the source of PBDEs to the hands may be dust particles. However, PBDE hand residues may also be a result of direct contact with PBDE-laden products, leading to adsorption to the skin surface oils. Repeated wipe sampling from three individuals suggests that sigmaPBDE levels on the hand may be relatively consistent for some individuals but not for others. Furthermore, levels of sigmaPBDEs were greater on the bottom of the hands relative to the top of the hands. Using these values we have calculated potential human exposure from hand-to-mouth contact. The median exposure estimates for children and adults are 1380 and 154 ng/day, respectively, whereas the 95th percentile exposure estimates were 6090 and 677 ng/day, respectively. These estimates are greater than dietary intake rates and suggest hand-to-mouth contact may be a key exposure route for PBDEs.

Quantified outdoor micro-activity data for children aged 7–12-years old

“…Mouthing duration of hands, toys and non-dietary objects also decreased with age among the 1-12-year-old children. However, most current methods to estimate non-dietary ingestion incorporate frequency but not mouthing duration (Zartarian et al, 2000;Canales and Leckie, 2007;Nicas and Best, 2008;Stapleton et al, 2008;Tulve et al, 2010). It is likely with a longer mouthing duration that a greater surface area of the object or hand would be mouthed, which could lead to a greater amount of ingested contaminant.…”

“…Mouthing and hand contact frequencies are key parameters for estimating non-dietary ingestion and dermal exposure (Zartarian et al, 2006;Nicas and Best, 2008;Stapleton et al, 2008;Julian et al, 2009;Schleier et al, 2009;Macedo et al, 2010;Tulve et al, 2010), as well as soil/dust ingestion rates (Ö zkaynak et al, 2010) critical for most hazardous site clean-up risk assessments including Superfund sites (US EPA, 2004). Several studies have quantified these mouthing and hand contact behaviors in children (Zartarian et al, 1997aBrinkman et al, 1999;Reed et al, 1999;Freeman et al, 2001Freeman et al, , 2005Tulve et al, 2002;AuYeung et al, 2004;Black et al, 2005;Auyeung et al, 2006;Beamer et al, 2008); however, we know of only one other study that has reported any data on children over 6 years of age (Freeman et al, 2001).…”

Indoor Contamination with Hexabromocyclododecanes, Polybrominated Diphenyl Ethers, and Perfluoroalkyl Compounds: An Important Exposure Pathway for People?

“…Better characterization of human dust ingestion rates constitutes a significant research gap. As it is thought dust ingestion occurs primarily via hand-to-mouth contact, a recently explored approach used contamination present in hand wipes to estimate exposure to PBDEs (86). However, uncertainties remain including the frequency and duration of hand-tomouth events and efficiency of hand-to-mouth transfer.…”

PBDE exposure from food in Ireland: optimising data exploitation in probabilistic exposure modelling

“…Previous studies have shown that oral and dermal uptake of dust and soil, as well as ingestion of food are the main exposure pathways contributing to the total human exposure to PBDEs (Jones-Otazo et al, 2005;Harrad et al, 2008;Lorber, 2008;Stapleton et al, 2008;Fraser et al, 2009;Johnson-Restrepo and Kannan, 2009). The dust pathways tend to be more influential than food intake in North America (Jones-Otazo et al, 2005;Lorber, 2008), but not necessarily in Europe, where the food pathway can be dominant for tri-hexa-BDEs (Harrad et al, 2008).…”