Pollution Characteristics and Intake Risks of Four Groups of Halogenated Aromatic Compounds in Representative Edible Fish from South China.

Halogenated aromatic compounds (HACs) exhibit environmental ubiquity, persistence, bioaccumulation, and diverse toxic effects, prompting widespread concern about their pollution and potential risks. This study investigated four categories of typical HACs in fish samples from five common species in South China. Results showed that the mean±standard deviation (range) of toxic equivalent quantity (TEQ) of polychlorinated dibenzo-p-dioxins/ furans (PCDD/Fs), dioxins-like polychlorinated biphenyls (DL-PCBs), polybrominated dibenzo-p-dioxins/furans (PBDD/Fs), and total dioxins (dioxins) were (0.0680±0.3230) pg⋅g^-1(0 ~2.21 pg⋅g^-1), (0.118±0.124) pg⋅g^-1 (0.000451 ~0.528 pg⋅g^-1), (0.139±0.164) pg⋅g^-1 (0.00882 ~0.917 pg⋅g^-1), and (0.325±0.366) pg⋅g^-1 (0.0409 ~ 2.30 pg⋅g^-1) (based on wet weight), respectively. All values were below the specified TEQ limit set by the European Union (EU) for dioxins in fish. Among the five fish species, mandarin fish exhibited the highest total TEQ and intake risk, followed by eel and catfish, while perch had the lowest. However, no statistical differences were observed in the TEQ among these five fish species. In comparison to global data, the concentrations of polybromodiphenyl ethers (PBDEs) in these fish samples (0.347±0.297) ng⋅g^-1(0.0191 ~ 1.40 ng⋅g^-1) (based on wet weight) were at moderate or low levels with a changing trend among species: salmon>eel>perch>mandarin fish>catfish. The PCDD/Fs in these fish samples were predominantly high-chlorinated, possibly originating from PCDD/Fs-polluted feed and the use of pentachlorophenol/pentachlorophenol sodium. PCB-118 and PCB-105 were the dominant congeners of DL-PCBs in these samples, primarily sourced from commercial PCB products and various metal smelting processes. The sources of PBDEs in these fishes included commercial PBDE mixtures and the debromination of high-brominated PBDEs. PBDD/Fs showed dominance in high-brominated PBDFs, and their pollution was closely associated with PBDEs. The intake carcinogenic and non-carcinogenic risk values of these four HACs via fish consumption ranged from 6.56x 10^-6 to 2.87x 10^-5 and 0.0314 to 0.114, respectively, for the residents from South China, with higher values for children compared to teenagers and adults. PBDD/Fs contributed significantly higher total TEQ and intake risks (45.6% on average) than the other HACs, emphasizing the ongoing need for continuous attention to their pollution in biota and associated risks. [ABSTRACT FROM AUTHOR]