General biological effects of TCDD in laboratory animals.

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is reported to be one of the most toxic chemicals known. There has been variation in such reported toxic parameters as single oral LD50 dose, range of time interval from dosing until death, and toxic manifestations which an animal exhibits (1-4). It seemed most appropriate, therefore, that the mean values and ranges of these and other general biological parameters be determined under the experimental condition to which animals are exposed at this Institute.