Regulated and unregulated halogenated flame retardants in peregrine falcon eggs from Greenland

Median levels of regulated flame retardants, i.e. polybrominated diphenyl ethers (PBDEs), brominated biphenyl (BB) 153 and hexabromocyclododecane (HBCD) in 33-48 eggs of peregrine falcons (Falco peregrinus) from Greenland were 1900, 359 and 5.98 ng/g lipid weight (lw) and generally intermediate to levels in North America and Europe. Unregulated flame retardants had lower median concentrations of 1.06 (2-ethylhexyl-2,3,4,5-tetrabromobenzoate, EH-TBB), 2.42 (1,2-bis(2,4,6-tribromophenoxy)-ethane, BTBPE), 0.52 (2,4,6-tribromophenyl 2,3-dibromopropyl ether, DPTE) and 4.78 (dechlorane plus) ng/g lw. Although these compounds are often considered as replacements for PBDEs, they were also present in eggs from the 1980s. BDE-209 was the only compound with a significant increase (+7.2% annual change) between 1986 and 2014, while BB-153 and DPTE decreased significantly (-8.0 and 2.8% annual change, respectively). Dechlorane plus showed a non-significant increase. Individual birds equipped with light-logging geolocators, confirmed the contaminant exposure over a large geographical area as the birds spend nearly equal time periods in their breeding and wintering grounds in Greenland and Central/South America, respectively, interrupted by 5-6 weeks of migration through North America.