octabromobiphenyl and Abnormalities--Drug-Induced

Extensive toxicological studies were carried out to define the probable hazard of octabromobiphenyl (OBB) to workers, users, and the environment. OBB had low acute toxicity in mammals and birds by various routes of administration. It was essentially non-irritating to rabbit eyes, non-irritating to human skin and caused only mild skin irritation and no sensitization in the guinea pig. OBB caused equivocal effects in the rat fetus. OBB was stored in the body fat of rats and caused liver enlargement at high single doses or low repeated doses. The studies indicate probable low safety factors in application and use and probable bioaccumulation. Hexabromobiphenyl (HBB) was more acutely toxic than OBB by skin absorption in the rabbit and caused liver enlargement at lower single doses.

Topics: Abnormalities, Drug-Induced; Animals; Biphenyl Compounds; Body Weight; Dermatitis, Contact; Diet; Environmental Exposure; Eye; Female; Fetus; Guinea Pigs; Hepatomegaly; Humans; Liver; Male; Organ Size; Polybrominated Biphenyls; Quail; Rabbits; Rats; Skin; Skin Absorption

Decabromodiphenyl oxide (DBDPO) and octabromobiphenyl (OBBP) perform well as fire-retardant additives for thermoplastics. Both compounds have low acute oral toxicity and low skin absorption toxicity. They are neither primary skin irritants or skin sensitizers and are only mildly irritating to the eyes. A 30-day dietary feeding study in rats established 8 mg DBDPO/kg-day as an unequivocal no-effect level and 80 mg/kg-day as a marginal effect level. A no-effect level was not established for OBBP in a comparative study. A 2-yr rat study providing 0.1 mg DBDPO/kg-day in the diet revealed the bromine concentration reached a plateau in the liver within 30 days, while the concentration in adipose tissue slowly increased. A comparable OBBP study revealed bromine concentration in the liver and adipose tissue increased steadily and rapidly with no attainment of a plateau during 180 days of the study. Neither compound produced an accumulation of bromine in other tissues. After administration of 14C DBDPO, all 14C activity was eliminated via the feces within 2 days. After administration of 14C OBBP, 62% was eliminated with a half-life of less than 24 hr; the half-life for the remainder was greater than 16 days. In a teratology study, 10, 100, or 1000 mg DBDPO/kg-day had no effect in rats. Reproductive capacity of rats was not effected at 3, 30, or 100 mg DBDPO/kg-day. No effects were observed on cytogenetic examination of bone marrow cells of parents and weanlings from the reproduction study.

Topics: Abnormalities, Drug-Induced; Acne Vulgaris; Adipose Tissue; Animals; Biphenyl Compounds; Bromine; Bromobenzenes; Chemical Phenomena; Chemistry; Diet; Erythema; Eye; Female; Fetus; Halogenated Diphenyl Ethers; Intubation, Gastrointestinal; Liver; Male; Phenyl Ethers; Polybrominated Biphenyls; Pregnancy; Rabbits; Rats; Reproduction