Toxicity of Chromium and Histological Effect of Gill on Carassius auratus

To study acute toxicities of chromium(Cr) to fish,which can offer reference for evaluating environmental quality and detecting environment,We studied the acute toxicities of chromium and the histological change of gill on Carassius auratus using statistics and histological methods,and stated the median lethal concentrations(LC50) and the safety concentrations(SC) . The results of acute toxicity showed that the LC50 at 24,48,72,96 hour were 387.1,370.9,281.9,200.2 mg/L,and SC is 102.176 mg/L. The results of histological observation showed that the cells of branchial leaflets fall off and branchial leaflets become thin. These results suggest that chromium is an heavy metal pollutant which have middling and high side toxicity on Carassius auratus,and damage its gill. The toxicity effection is boost up along with increase of the concentration of chromium in Carassius auratus.