Temporal Trends and Suspect Screening of Halogenated Flame Retardants and Their Metabolites in Blubbers of Cetaceans Stranded in Hong Kong Waters during 2013-2020

作者：Wang, Qi; Ruan, Yuefei^*; Jin, Linjie; Kot, Brian C. W.; Leung, Kenneth Mei Yee; Lam, Paul K. S.^*

来源：Environmental Science and Technology, 2023, 57(25): 9298-9308.

DOI：10.1021/acs.est.3c00684

• polybrominated diphenyl ethers
• Me-MeO-tetra-BDE
• high-resolution mass spectrometry
• south china sea
• marine mammal
• metabolites
• 2
• 3-dibromopropyl-2
• 4
• 6-tribromophenylether
• biomonitor

Halogenated flameretardants (HFRs) are a large classof chemicaladditives intended to meet flammability safety requirements, and atpresent, they are ubiquitous in the environment. Herein, we conductedthe target analysis and suspect screening of legacy and novel HFRsand their metabolites in the blubber of finless porpoises (Neophocaena phocaenoides; n = 70) and Indo-Pacifichumpback dolphins (Sousa chinensis; n = 35) stranded in Hong Kong, a coastal city in the South China Sea,between 2013 and 2020. The average concentrations of total targetHFRs (sigma HFRs) were 6.48 x 10(3) +/- 1.01 x10(4) and 1.40 x 10(4) +/- 1.51 x 10(4) ng/g lipid weight in porpoises and dolphins, respectively.Significant decreasing temporal trends were observed in the concentrationsof tetra-/penta-/hexa-bromodiphenyl ethers (tetra-/penta-/hexa-BDEs)in adult porpoises stranded from 2013-2015 to 2016-2020(p < 0.05), probably because of their phasingout in China. No significant difference was found for the concentrationsof decabromodiphenyl ether and hexabromocyclododecane, possibly dueto their exemption from the ban in China until 2025 and 2021, respectively.Eight brominated compounds were additionally identified via suspectscreening. A positive correlation was found between the concentrationsof tetra-BDE and methyl-methoxy-tetra-BDE (Me-MeO-tetra-BDE) (p < 0.05), indicating that the metabolism of tetra-BDEmay be a potential source of Me-MeO-tetra-BDE in marine mammals. @@@ Concentrations of tetra-/penta-/hexa-BDEsin the bubblerof cetaceans in Hong Kong waters decreased over the period of 2013-2020,probably due to the phasing out of these chemicals in China. Giventhe concentrations of tetra-BDE and Me-MeO-tetra-BDE in the bubblerwere positively correlated, the metabolism of tetra-BDE may be a possiblesource of Me-MeO-tetra-BDE in marine cetaceans.