The effects of exposure to water soluble fractions of crude oil on the histology and selected histochemical parameters of the liver of Atlantic croaker

Abstract

Micropogon undulatus L. (Atlantic croaker) were sampled from an estuary and selected offshore sites in the Gulf of Mexico. Groups of five fish from the estuarine sample were exposed to 5% and 10% dilutions of the water soluble fraction (WSF) of southern Louisiana crude oil for 1, 3, 7, 14 and 21 days. Histology and selected histochemical parameters of liver sections from the offshore, estuarine, and WSF exposed fish were evaluated. The histology of Atlantic croaker liver sections differed from that previously reported for other marine and freshwater species. The parenchyma was arranged in tubular units similar to those of the primitive marine hagfish liver but also contained features of more modern freshwater fish livers. This liver structure may have resulted from evolution to accomodate for the marine environment as teleosts probably entered the sea from freshwater. Pigments in the liver probably resulted from disturbances in lipid metabolism which affected oxidative pathways of the hepatic lipid. ...