Hypothyroidism in Workers Exposed to Polybrominated Biphenyls

THE polybrominated biphenyls (PBB's) and polybrominated biphenyl oxides (FBBO's) are brominated hydrocarbons that have been used commercially as fire retardants. PBB's in particular are highly lipotropic and are not readily metabolized. As a result, they remain in adipose tissue for extended periods. Concern over toxic effects of PBB's on human beings arose when they were accidentally fed to livestock in Michigan in 1973.1 In August, 1978, a comprehensive medical evaluation was conducted on workers from a plant that manufactured a PBB, decabromobiphenyl, and a PBBO, decabromobiphenyl oxide, and on control groups of workers from other industries. The plant has manufactured . . .