1,2,3,7,8-PeCDD was administrated to juvenile goldfish (Carassius auratus) by peritoneal injections to explore the acute lethality and
endocrine e ects of 1,2,3,7,8-PeCDD in vivo. The value of acute median lethal dosage (LD50) of 1,2,3,7,8-PeCDD was determined in
acute lethality tests. The endocrine e ect of 1,2,3,7,8-PeCDD, whose exposed concentrations were determined based on the LD50 (1.84
mg/kg), was studied by measuring the plasma vitellogenin (Vtg) content in juvenile male goldfish with enzyme-linked immunosorbent
assays (ELISA). Due to its significant induction of the plasma Vtg after one week’s exposure in vivo in the 1/2 LD50 and LD30 groups,
1,2,3,7,8-PeCDD might be one of the important contributors to the estrogenic e ect of PCDDs in the environment. The values of 1/2
LD50 and LD30 were within the range of the e ective dosages of 1,2,3,7,8-PeCDD, indicating that there was a certain relationship
between the estrogenic e ective dosages and the LD50.