摘要:The acute toxicity of Water Soluble Fraction (WSF) of crude oil on Chironomus and mosquito larvae were evaluated to determine its effect on their survival rate. The larvae were exposed to acute concentration of WSF of crude oil (20.0, 10.0, 5.0 and 0.0 ml L-1) during the 48 h exposure in a static bioassay medium. Mortality was found to increase with exposure time and concentration. The 48 h Median Lethal Concentration (MLC) were 5.75 and 6.61 ml L-1 for mosquito and Chironomus larvae, respectively. However, the 48 h Median Lethal Time (MLT) for the different concentrations were 18.20 h for 20 ml L-1, 28.20 h for 10 ml L-1 and 48 h for 5 ml L-1 and 26.80 and 41.80 h for 20 and 10 ml L-1, respectively. Comparatively, mosquito larvae were more sensitive to the WSF of crude oil compared to the Chironomus larvae as shown in this finding.