The lack of effect of tertiary butylhydroquinone on prothrombin time in male rats.

The potential for tertiary butylhydroquinone (TBHQ) to produce hemorrhagic death similar to that seen after butylated hydroxytoluene (BHT) treatment was tested in male rats. Groups of male rats were given three consecutive daily doses of 380, 760 or 1520 mg/kg/day BHT or 50, 100 or 150 mg/kg TBHQ. Twenty-four hours following the last dose, the rats were killed, blood was taken for prothrombin determinations and gross autopsies were performed. No evidence of hemorrhage was found in any of the animals. BHT caused a significant dose-dependent increase in prothrombin times, while the prothrombin times of the TBHQ rats were comparable to the controls. Since hypoprothrombinemia plays a major role in producing hemorrhagic death, these data indicate that the potential for THBQ to have such an effect is low.