Brominated and chlorinated dioxins, PCBs and brominated flame retardants in Scottish shellfish: Methodology, occurrence and human dietary exposure

Abstract

The most commonly consumed shellfish species produced in Scotland - mussels, oysters and scallops - were investigated for the occurrence of a range of brominated and chlorinated contaminants in order to establish current levels and estimate human dietary exposure. Flesh from individual sub-samples was representatively pooled and 35 composites were analysed for brominated and chlorinated dioxins (PBDD/Fs, PCDD/Fs), brominated and chlorinated biphenyls (PBBs, PCBs), polybrominated diphenyl ethers (PBDEs), hexabromocyclododecanes (HBCDs) and tetrabromobisphenol A (TBBPA). The analytical methodology used (13)C(12) labelled surrogates of the target compounds, with GC coupled to (usually) high resolution MS, and LC-MS/MS for HBCD and TBBPA analysis. Positive identifications were made in the majority of samples for most analytes with the exception of TBBPA and most PBDD congeners measured. None of the levels detected for PCDD/F and PCB were above the maximum permitted levels specified in European Union regulations. The levels of brominated furans predominated over brominated dioxins, reflecting the environmental distribution and source emission profiles of these contaminants, and relatively high levels of the tri-brominated congeners were observed. Levels of the flame retardant chemicals reflected current and legacy use, with appreciable concentrations of PBDEs and HBCDs (predominantly alpha-HBCD) but far lower levels of PBBs. TBBPA was not detected in any of the species. In general, mussels and oysters displayed relatively higher levels of contamination than scallops, although the gonad tissue of the latter showed significant levels of brominated dioxins. The estimated adult dietary intakes of PCDD/Fs and PCBs arising from the consumption of a typical portion of these foods in combination with an otherwise average UK diet were in the range 0.5-0.6 pg World Health Organisation (WHO)-toxic equivalent (TEQ)(2005)/kg bodyweight per day. These estimated dietary intakes are well within the Tolerable Daily Intake for dioxins and dioxin-like PCBs of 2 pg WHO-TEQ(2005)/kg bodyweight/day endorsed by the independent expert Committee on Toxicology of Chemicals in Food, Consumer Products and the Environment. The corresponding intakes for sumPBDEs and sumHBCDs were 5.6-6.1 and 5.9-7.9 ng/kg bodyweight/day respectively.

Organic Contaminant Content and Physico-Chemical Characteristics of Waste Materials Recycled in Agriculture

“…The method used for the preparation, extraction and analysis of samples [11,12] forms part of the CEN method-EN16215:2012 for PCDD/F and PCB analysis. In brief, samples were fortified with 13 C-labelled analogues of target compounds and exhaustively extracted using mixed organic solvents.…”

Level and congener profiles of polybrominated dibenzo-p-dioxins and dibenzofurans in the atmosphere of Beijing, China

“…PBDD/Fs, which are PCDD/F analogs with all chlorine atoms substituted by bromine (WHO, 1994), have received less concern than PCDD/Fs, and data about their environmental level are very scarce. Up to now, PBDD/Fs have been identified and determined in several matrices including: ambient air in Kyoto (Hayakawa et al, 2004), Osaka (Ohta et al, 2002;Watanabe et al, 1995), Shanghai (Li et al, 2008) and at different locations in Taiwan (Wang et al, 2008), at electronic waste dismantling areas in China (Li et al, 2007), in plastics from waste TV sets (Tasaki et al, 2004), as a constituent of flue gases (Wang and Chang-Chien, 2007;Schüler and Jager, 2004), fly ash (Weber and Kuch, 2003;Hagberg et al, 2005;Sovocool et al, 1989;Schwind et al, 1988), sediments (Watanabe et al, 1995;Choi et al, 2003a,b;Hagberg et al, 2005), diet samples (Nomura et al, 2007), shellfish (Fernandes et al, 2008), fish (Ashizuka et al, 2008), adipose tissue (Choi et al, 2003a,b), human milk (Ohta et al, 2002), and blood from people with occupational exposure (Zober et al, 1992). Concerns about PBDD/Fs have increased because brominated flame retardants (BFRs) are extensively used in a variety of materials and are miscible with most plastics.…”

Levels and Congener Profiles of Particle-bound Polybrominated Dibenzo-p-dioxins/furans (PBDD/Fs) in Ambient Air around Guangzhou, China

“…A certain number of reports and conferences have showed the occurrence of PBDD/Fs in ambient air (Hayakawa et al 2004;Li et al 2007Li et al , 2008Wang et al 2008), consumer products like plastics and TV sets (WHO 1998), sediments (Choi et al 2003a;Ren et al 2009), biota samples (Fernandes et al 2008) and even human samples (Choi et al 2003b), which proved that PBDD/Fs were ubiquitous in the environment. Toxicity equivalency quantity (TEQ) contributed by PBDD/Fs counted up to 15% of the total dioxin TEQ of five analyzed persistent organic pollutants (POPs) (Jogsten et al 2010).…”