Development of a Carcinogen Assay System Utilizing Estuarine Fishes

摘要

The objective of this project was the development of systems to assay the effects of chemical carcinogens on marine teleosts. It was determined that the LC-50 for benzidine with respect to Cyprinodon variegatus was ca. 64 ppm. Weekly contaminations of 1 ppm benzidine caused some individuals to develop proliferative liver lesions. Exposure of C. variegatus early embroyos produced the following anomalies at concentrations of 50 ppm and above: tubed heart syndrome with distended pericardia, poor circulation, sparse distribution of melanophores, inability to hatch, abnormal head morphology, scoliosis, and faint RBC pigmentation. Chronic exposure of a cell line from Archosargus probatocephalus to benzidine and benzo(a)pyrene produced mutagenic effects. Two novel techniques were developed to study the effects of carcinogens on C. variegatus at the cellular level -- an aseptic embryo technique and an embryo-primary cell culture technique. Standard immunological techniques were miniaturized to study the immune system of C. variegatus. Serum electrophoresis disclosed that the serum proteins of benzidine-exposed fish differed from unexposed controls.