title: In vitro assessment of mutagenicity and clastogenicity of BDE-99, a pentabrominated diphenyl ether flame retardant.
abstract: Polybrominated diphenyl ethers (PBDEs), which are widely used as flame retardants, are considered persistent organic pollutants. To date, the available toxicological data on PBDEs are limited and were primarily obtained by studying technical blends. The present study was undertaken to investigate the genotoxicity of the pure congener 2,2',4,4',5-brominated diphenyl ether (BDE-99), one of the major isomers present in penta-commercial products. Bacterial reverse mutation assays in Salmonella typhimurium strains TA98 and TA100 and in Escherichia coli WP2 uvrA, and the Allium cepa chromosome aberration test were carried out to evaluate mutagenicity and clastogenicity. The experimental design also involved testing a well-known polychlorinated biphenyl (PCB) mixture, Aroclor(R) 1254, which is structurally related to PBDEs. BDE-99 was negative in the bacterial mutagenicity assays, with and without S9 mix. Also, the frequency of structural chromosome aberrations was not significantly higher than the control and no signs of cytotoxicity were observed in BDE-99-treated A. cepa. Aroclor(R) 1254 was not mutagenic, but it induced a significant increase in chromosomal aberrations in A. cepa. In conclusion, BDE-99 was not mutagenic in S. typhimurium or E. coli, or clastogenic in A. cepa; however, the possibility that PBDEs might act through an epigenetic mechanism cannot be excluded.
authors.affiliation: Department of Pharmacology of Natural Substances and General Physiology, University of Rome La Sapienza, Rome, Italy.
authors.forename: Maria G
authors.initials: MG
authors.lastname: Evandri
authors.forename: Sabina
authors.initials: S
authors.lastname: Mastrangelo
authors.forename: Lucio G
authors.initials: LG
authors.lastname: Costa
authors.forename: Paola
authors.initials: P
authors.lastname: Bolle
mesh_terms: D000490:Allium / Q000187:drug effects; D001140:Aroclors / Q000633:toxicity; D002869:Chromosome Aberrations; D004249:DNA Damage; D004785:Environmental Pollutants / Q000633:toxicity*; D004926:Escherichia coli / Q000187:drug effects; D055768:Halogenated Diphenyl Ethers; D009152:Mutagenicity Tests; D009153:Mutagens / Q000633:toxicity*; D010647:Phenyl Ethers / Q000633:toxicity*; D012486:Salmonella typhimurium / Q000187:drug effects
chemical_list: C477694:2,2',4,4',5-brominated diphenyl ether; D001140:Aroclors; D004785:Environmental Pollutants; D055768:Halogenated Diphenyl Ethers; D009153:Mutagens; D010647:Phenyl Ethers