Submitted to: International Symposium on Pollutant Responses in Marine Organisms
Publication Type: Abstract Only
Publication Acceptance Date: March 27, 1999
Publication Date: April 25, 1999
Citation: EVANS, J.J., SHOEMAKER, C.A., KLESIUS, P.H. IN VIVO AND IN VITRO EFFECTS OF BENZOTHIAZOLE ON SHEEPSHEAD MINNOW. TENTH INTERNATIONAL SYMPOSIUM ON POLLUTANT RESPONSES IN MARINE ORGANISMS. 1999. Technical Abstract: Benzothiazole, a common chemical associated with tire manufacturing and industrial wastewater, was determined to be a principal component of both freshwater and estuarine tire leachate, a neurotoxicant in in vivo estuarine studies. The purpose of this study was to determine if benzothiazole was responsible for the observed neurotoxicity from tire leachate due to its presence in leachate samples and the lack of literature regarding its toxic effects to aquatic animals. Larval sheepshead minnows (Cyprinodon variegatus) were exposed to 3.75, 7.5, 15, 30, and 60 ppm benzothiazole in a toxicity bioassay and examined histologically. Mortality of sheepshead minnow occurred after 5 days of exposure to 60 ppm (LC50=39). Histologically, the central nervous system did not show the severe cellular damage as seen from tire leachate exposure. A tetrazolium salt (MTT) in vitro assay was performed on primary cultures of brain cells from sheepshead minnows and tilapia (Oreochromis niloticus) and two epithelial cell lines exposed to benzothiazole at 1 and 4 days. In vitro results indicated primary cultures of sheepshead brain cells were more sensitive than tilapia brain cells at all benzothiazole concentrations at 1 and 4 days but not as sensitive as the epithelial cell lines. Significant cytotoxicity to the epithelial cell lines was noted at 30 and 60 ppm concentrations. The present study indicates that benzothiazole does not appear to be a neurotoxicant.