title: Dioxin-like potency of HO- and MeO- analogues of PBDEs' the potential risk through consumption of fish from eastern China.
abstract: Polybrominated diphenyl ethers (PBDEs) and their analogues, such as hydroxylated PBDE (HO-PBDEs) and methoxylated PBDE (MeO-PBDEs) are of interest due to their wide distribution, bioaccumulation and potential toxicity to humans and wildlife. While information on the toxicity/biological potencies of PBDEs was available, information on analogues of PBDEs was limited. Dioxin-like toxicity of 34 PBDEs analogues was evaluated by use of the H4IIE-luc, rat hepatoma transactivation bioassay in 384-well plate format at concentrations ranging from 0 to 10 000 ng/mL. Among the 34 target analogues of PBDEs studied here, 19 activated the aryl hydrocarbon receptor (AhR) and induced significant dioxin-like responses in H4IIE-luc cells. Efficacies of the analogues of PBDEs ranged from 5.0% to 101.8% of the maximum response caused by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD-max) and their respective 2,3,7,8-TCDD potency factors (ReP(H4IIE-luc)) ranged from 7.35 × 10(-12) to 4.00 × 10(-4), some of which were equal to or more potent than some mono-ortho-substituted PCBs (TEF-(WHO) = 3 × 10(-5)). HO-PBDEs exhibited greater dioxin-like activity than did the corresponding MeO-PBDEs. Analogues of PBDEs were detected mostly in marine organisms. Of these 11 detected analogues of PBDEs, 6 were found to have measurable dioxin-like potency. Though some analogues of PBDEs exhibited significant dioxin-like potency as measured by responses of the H4IIE-luc transactivation assay, concentrations of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) equivalents ((PBDEs analogues)TEQ(H4IIE-luc)), calculated as the sum of the product of concentrations of individual PBDE and their ReP(H4IIE-luc), were less than the tolerance limit proposed by European Union and the oral reference dose (RfD) derived by U.S. Environmental Protection Agency, respectively. (Hazard Quotients (HQ) < 0.005) Additional investigations should be conducted to evaluate the toxic potencies of these chemicals, especially for 2'-MeO-BDE-28, 4-HO-BDE-90, 6-HO-BDE-47, and 6-MeO-BDE-47, which had been detected in other environmental media, including human blood.
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse & School of the Environment, Nanjing University, Nanjing, China.
authors.forename: Guanyong
authors.initials: G
authors.lastname: Su
authors.forename: Jie
authors.initials: J
authors.lastname: Xia
authors.forename: Hongling
authors.initials: H
authors.lastname: Liu
authors.forename: Michael H W
authors.initials: MH
authors.lastname: Lam
authors.forename: Hongxia
authors.initials: H
authors.lastname: Yu
authors.forename: John P
authors.initials: JP
authors.lastname: Giesy
authors.forename: Xiaowei
authors.initials: X
authors.lastname: Zhang
mesh_terms: D000818:Animals; D000840:Anisoles / Q000633:toxicity; D002681:China; D004147:Dioxins / Q000633:toxicity*; D005396:Fish Products; D005399:Fishes; D005506:Food Contamination; D005618:Fresh Water; D055768:Halogenated Diphenyl Ethers / Q000737:chemistry / Q000633:toxicity*; D006801:Humans; D010636:Phenols / Q000633:toxicity; D011075:Polybrominated Biphenyls / Q000633:toxicity; D000072317:Polychlorinated Dibenzodioxins / Q000633:toxicity; D051381:Rats; D018336:Receptors, Aryl Hydrocarbon / Q000819:agonists / Q000378:metabolism; D018570:Risk Assessment; D018675:Toxicity Tests
chemical_list: C496823:2-(2',4'-dibromophenoxy)-3,5-dibromoanisole; D000840:Anisoles; D004147:Dioxins; D055768:Halogenated Diphenyl Ethers; D010636:Phenols; D011075:Polybrominated Biphenyls; D000072317:Polychlorinated Dibenzodioxins; D018336:Receptors, Aryl Hydrocarbon; C085794:3,5-dibromo-2-(2,4-dibromophenoxy)phenol; C533760:tribromodiphenyl ether 28