Tissue concentrations and induction of a hepatic monooxygenase in male Wistar rats after repeated doses of defined polychlorinated dibenzo-p-dioxin and dibenzofuran (PCDDs and PCDFs) mixtures.

Two groups of male Wistar rats were treated 16 times (every 3rd day) subcutaneously with a defined mixture of polychlorinated dibenzo-p-dioxins (PCDDs) or of polychlorinated dibenzofurans (PCDFs). These mixtures contained no measurable amount of 2,3,7,8-TCDD. Each single dose was calculated to contain either 57 ng I-TEq (international 2,3,7,8-T4CDD toxicity equivalencies)/kg body weight of the PCDD mixture or 39 ng I-TEq/kg body weight of the PCDF mixture.