Emerging halogenated flame retardants in the indoor environment

Abstract

Indoor environments are considered an important contributor to external human exposure to halogenated flame retardants (HFRs) due to the large amounts of chemicals currently incorporated in indoor equipment and the time humans spend every day in indoor environments. In this chapter, the presence and use of novel brominated flame retardants (NBFRs), dechlorane plus (DPs), chlorinated organophosphorus flame retardants (Cl-PFRs) and chlorinated paraffins (CPs) in indoor dust, air and consumer products collected from different indoor microenvironments (homes, public indoor spaces, and vehicles) are discussed. While data on the concentrations of HFRs in indoor dust and air are widely available, figures are still scarce for consumer products, such as textiles and foams, furnishings, flooring, electric and electronic products and building materials. This knowledge gaps still represents the biggest obstacle in linking eventual sources of contamination to the presence and chemical patterns in indoor dust and air.

Seasonal variation of short-, medium- and long-chain chlorinated paraffin distribution in Belgian indoor dust

“…Importantly, the ∑ CP (C 10-20 ) concentrations measured in this study were also one to three orders of magnitude higher than those of brominated and organophosphate flame retardants (BFRs and OPFRs, respectively) reported in indoor dust from Belgium (Van den Eede et al, 2011;Ali et al, 2011;D'Hollander et al, 2010;Roosens et al, 2009) and other studies, broadly (Poma et al, 2020). In Belgian house dust samples, the sum of nine OPFRs ranged 1.92 to 94.7 μg/g (median 13.3 μg/ g) (Van den Eede et al, 2011), decabromodiphenyl ether (BDE-209) ranged < 0.005 to 5.3 μg/g (median 0.31 μg/g), hexabromocyclododecanes (HBCDs) ranged 0.005 to 42.7 μg/g (median 0.13 μg/g) (D'Hollander et al, 2010) and the highest individual measurement among five novel BFRs was 5.0 μg/g of bis(2-ethylhexyl)-3,4,5,6-tetrabromophthalate (TBPH) (Ali et al, 2011).…”

“…It is important to note that exposure estimations reported here, based on the assumption of 100 % bioaccessibility of ingested CPs, will necessarily overestimate true internal uptake, with experimental evidence suggesting homologue specific bioaccessibility of dust borne SCCPs and MCCPs to range between 7.9 and 45.8 % (Du et al, 2021). Conversely, CP exposure via dust ingestion in the workplace and vehicles, where concentrations of similar compounds, such as flame retardants, have typically been higher than in homes (Poma et al, 2020;He et al, 2019;McGrath et al, 2022;McGrath et al, 2018), is not accounted for in the present study. The higher CP body burdens and associated increased health risks experienced by toddlers from ingestion of contaminated indoor dust results from the combined factors of smaller body weight and behaviours which accelerate ingestion of dust such as mouthing of toys and objects.…”

“…Although manufacture and import of CP mixtures and CP-treated materials have been restricted to levels of 1 and 0.15 % w/w SCCP impurities, respectively, in the EU since 2015 (EC, 2015), such limits on imported goods may be difficult to practically enforce. The combined presence of both SCCPs and MCCPs has, in any case, been reported in consumer goods purchased in Belgium during 2019 (McGrath et al, 2021c) and elsewhere (Poma et al, 2020), whether due to intentional incorporation or via recycled materials sources.…”

Short- and Medium-Chain Chlorinated Paraffins in Polyvinylchloride and Rubber Consumer Products and Toys Purchased on the Belgian Market

“…Release of SCCPs via volatilization has been evidenced from PVC flooring during thermal treatment by Zhan et al [17] while SCCPs, MCCPs and LCCPs have been observed to migrate from other treated materials [9,15,18]. Such leaching from CP-treated products can lead to contamination of environmental matrices and indoor dust, resulting in human exposure [10,19,20]. For items such as toys or sporting equipment, exposure via direct dermal contact or mouthing by children and toddlers must also be considered.…”

Detection of Bromochloro Alkanes in Indoor Dust Using a Novel CP-Seeker Data Integration Tool

“…Chlorinated paraffins (CPs), mostly composed of polychlorinated alkanes (PCAs), are a complex mixture of tens of thousands of individual compounds which have been used as plasticizers, flame retardants and lubricants in a wide variety of consumer goods and materials including polyvinyl chloride, rubber, adhesives, sealants and textiles. , Global production of PCAs has increased substantially during recent decades with recent total manufacture predicted to exceed one million tonnes per year as of 2020 . PCAs may be released from materials via volatilization, abrasion or direct transfer to other matrices and have been identified as one of the major plasticizer contaminants in indoor dust, resulting in human exposure via inadvertent dust ingestion. − Commercial CP products are typically categorized by the most prominent carbon chain length of PCA constituents as short- (C 10–13 ), medium- (C 14–17 ), and long- (C ≥18 ) chain CPs (SCCPs, MCCPs and LCCPs, respectively) . SCCP, MCCP, and LCCP groups have each exhibited bioaccumulative and toxic endocrine disrupting properties − and have been detected globally in human blood and breastmilk in numerous studies.…”