Presence and partitioning properties of the flame retardants pentabromotoluene, pentabromoethylbenzene and hexabromobenzene near suspected source zones in Norway

Abstract

The brominated flame retardants (BFRs), pentabromotoluene (PBT), pentabromoethylbenzene (PBEB) and hexabromobenzene (HBB), exhibit physical-chemical properties similar to other persistent organic pollutants, and have been in use as flame retardants for several decades. Data on these BFRs in diverse environmental samples can be found in studies from the 1970s and 1980s, as well as in recent years, though very little in the years in between. Due to a lack of data, the cause for the apparent re-emergence of these BFRs in recent studies is unclear, and could reflect changes in production volumes, accumulation of transformation products from BFR precursors, improved analytical techniques or simply a re-emergence in concern. Very little data are available on their environmentally relevant partitioning properties, which could help to explain the occurrence and fate of these BFRs. In this study we analysed for the presence of HBB, PBT, and PBEB in diverse environmental samples from potential Norwegian BFR source zones. Additionally, environmental partitioning properties of these BFRs as well as brominated benzenes were estimated and validated using experimental data for brominated benzenes. Of the three BFRs, HBB was identified in detectable quantities at most source zones, PBEB only near a metal recycling factory, and PBT only in a few additional locations from where PBEB was detected. Data from this study show that HBB is likely widely distributed, as verified both by chemical analysis and estimated properties. Measured HBB levels in wastewater treatment plants indicate that the treatment practices used in the study locations are not effective at lowering HBB levels, perhaps due to association with low density suspended solids (e.g. microplastics).

Scientific Opinion on Emerging and Novel Brominated Flame Retardants (BFRs) in Food

“…Comparable levels in eggs from across the Great Lakes suggest common origin of exposure, possibly via atmospheric transport. Arp et al (2011) analysed fish liver, crab and blue mussel samples from three sites in Norway, but HBB could not be identified above the LOQ (0.1 ng/g w.w.).…”

“…The corresponding concentrations at a rural site were 0.10-4.80 pg/m 3 , with an arithmetic mean of 0.75 pg/m 3 . Arp et al (2011) analysed sediment samples outside a metal recycling plant in Drammen (Norway) and found 0.028 ± 0.036 ng/g dry weight (LOD: 0.004, LOQ: 0.01). Körner et al (2011) found PBEB in sewage sludge in Bavaria in concentrations ranging from 0.002 (LOD) to 0.52 ng/g dry weight with a mean of 0.022 ng/g dry weight.…”

“…At the e-waste site the concentrations of PBEB (gas and particle bound combined) were 0.29-867 pg/m 3 , with an arithmetic mean at 41.0 pg/m 3 . The corresponding concentrations at a rural site were 0.10-4.80 pg/m 3 , with an arithmetic mean of 0.75 pg/m 3 Arp et al (2011). analysed sediment samples outside a metal recycling plant in Drammen (Norway) and found 0.028 ± 0.036 ng/g dry weight (LOD: 0.004, LOQ: 0.01) Körner et al (2011).…”

“…Pools of herring gull eggs (Larus argentatus) collected in 2004 from six sites in the Great Lakes were considered in a study byGauthier et al (2007). The maximum concentration of PBEB was 1.4 ng/g w.w Arp et al (2011). analysed fish liver, crab and blue mussel samples from three sites in Norway but PBEB could not be identified above the LOQ (0.1 ng/g w.w.).Muñoz-Arnanz et al (2010) report data on the occurrence of BFRs in eggs of white stork (Ciconia ciconia) obtained from two colonies in Spain.…”

Polybrominated diphenyl ethers, dechlorane plus, and polychlorinated biphenyls in tree bark near the upper Yellow River, China

“…Thus, the chemical industry is likely to be a source of PBDEs. Sample 11, collected in Baiyin City, with the highest concentration, [31,32].…”