Current-use halogenated and organophosphorous flame retardants:A review of their presence in Arctic ecosystems

Since the ban of polybrominated diphenyl ethers(PBDEs)and hexabromocyclododecane(HBCDD),other flame retardants may be increasingly used.Thirty-one current-use halogenated(HFRs)and 24 organophosphorous flame retardants(PFRs)have been sought in Arctic ecosystems so far.Air measurements provide evidence of long-range atmospheric transport for the majority of these compounds,with much higher concentrations for PFRs than for HFRs.Some HFRs,i.e.bis(2-ethylhexyl)-tetrabromophthalate(BEH-TEBP),2-ethylhexyl-2,3,4,5-tetrabromobenzoate(EH-TBB)and hexabromobenzene(HBBz),had air concentrations comparable to those of PBDEs in some studies.Complementary data for seawater and ice indicate dry deposition of HFRs,while net volatilization from seawater was observed for some PFRs.Studies in the marine environment indicate a wide presence of HFRs in marine biota,but generally at low levels,i.e.typically lower than those of PBDEs.Exceptions exist,namely 2,4,6-tribromophenyl 2,3-dibromopropyl ether(TBP-DBPE)and decabromodiphenyl ethane(DBDPE),which were found in concentrations comparable to PBDEs in some species.The same was the case for 2,4,6-tribromophenyl allyl ether(TBP-AE)in a study from the terrestrial environment.PFRs generally had low concentrations in biota,probably due to metabolic transformation of PFR triesters,as suggested by in vitro studies.Elevated PFR concentrations occurred in some individuals,generally indicating a larger variability of PFRs in biota than found for HFRs.The commercially important tetrabromobisphenol A(TBBPA)was only detected sporadically,and only in abiotic matrices.

A review of chlorinated paraffin contamination in Arctic ecosystems

Chlorinated paraffins(CPs)present a complex mixture of congeners which are often analysed and assessed as short-,medium-and long-chain CPs,i.e.SSCCP(C10eC13),SMCCP(C14eC17)and SLCCP(
C18).Their complexity makes the chemical analysis challenging,in particular in terms of accurate quantification,but promising developments involving ultra-high resolution mass spectrometry have been presented lately.Most Arctic data exist for SCCPs,while LCCPs have not yet been studied in the Arctic.SSCCP concentrations in Arctic air often exceeded those of SMCCP,usually with a predominance of the most volatile C10 congeners,and of banned persistent organic pollutants(POPs),such as polychlorinated biphenyls(PCBs).The presence of SCCPs and MCCPs in Arctic air,as well as in the Antarctic and in the remote regions of the Tibetan plateau,provides evidence of their long-range transport including sufficient environmental persistence to reach the Arctic.Arctic vegetation accumulated SCCPs partly from air and partly through root uptake from soil,with consequences for the SCCP profile found in Arctic plants.No results have yet been reported for CPs in terrestrial Arctic animals.Results for freshwater sediment and fish confirmed the long-range transport of SCCPs and MCCPs and documented their bioaccumulation.Where additional PCB data were available,SPCB was usually higher than SSCCP in freshwater fish.Both SCCPs and MCCPs were widely present in marine Arctic biota(e.g.mussels,fish,seabirds,seals,whales,polar bears).In mussels and Atlantic cod,SMCCP concentrations exceeded those of SSCCP,while this was less clear for other marine species.Marine mammals and the long-lived Greenland shark roughly had SSCCP concentrations of 100e500 ng/g lipid weight,often dominated by C11 congeners.Biomagnification appeared to be more pronounced for SSCCP than for SMCCP,but more studies will be needed.Increasing SSCCP concentrations were observed in Arctic air and sediment over time,but not in beluga monitored since the 1980s.For both SCCPs and MCCPs,increasing concentrations over time have been shown in blue mussels and Atlantic cod at some,but not all stations.Indications exist of local sources of SCCPs in the Arctic,including Arctic settlements and research stations.In studies involving multiple locations,a general decrease of SCCP concentrations with increasing latitude or distance from point sources was observed as well as relatively more MCCPs at locations closer to potential CP sources.Monitoring of SCCPs and MCCPs has been initiated in some Arctic regions and will be important to assess the effect of recent regulations of SCCPs and the use of potential replacement chemicals.