摘要：The acute toxicity of Nigeria crude oil (Bonny Light), reference compound (Sodium Dodecyl Sulphate (SDS)), dispersant (Nalco-D4106) and dispersant-plus-crude oil to Tilapia guineensis were studied. Tests were conducted over a 96 h period after acclimatization of individual in the laboratory. There were initial ranges finding test to determine the concentrations of the toxicants to be administered on the test organisms in the definitive tests. The tests were semi-static bioassays in which the exposure media were replaced every 24 h, at which the T. guineensis were also examined for mortality. Tilapia guineensis were exposed to he following concentrations of crude oil (0, 40, 80, 160, 240 and 320 mg L-1), SDS (0, 5, 25, 50, 75 and 100 mg L-1), dispersant (0, 1500, 2000, 4000, 7500 and 10000 mg L-1) and dispersant-plus-crude oil (0, 540, 1080, 2160, 3240 and 4320 mg L-1). The 96 h LC50 of Bonny Light crude oil, SDS, dispersant and dispersant-plus-crude oil were 125.89, 25.12, 3162.28 and 1995.26 mg L-1, respectively. Sodium dodecyl sulphate was the most toxic of the toxicants and the dispersant (Nalco-D4106) reduced the toxicity of Bonny Light crude oil by 16 folds.
