title: Investigation of acute toxicity of chlorpyrifos-methyl on Nile tilapia (Oreochromis niloticus L.) larvae.
abstract: Chlorpyrifos-methyl, a wide-spectrum organophosphorus insecticide and potential toxic pollutant contaminating aquatic ecosystems, was investigated for acute toxicity. Larvae of the freshwater fish Nile tilapia (Oreochromis niloticus L.) were selected for the bioassay experiments. The experiments were repeated three times and the 96 h LC50 was determined for the larvae. The static test method for assessing acute toxicity was used. Water temperature was maintained at 25+/-1 degrees C. In addition, behavioral changes at each chlorpyrifos-methyl concentration were observed for the individual fish. Data obtained from the chlorpyrifos-methyl acute toxicity tests were evaluated using Finney's probit analysis statistical method. The 96 h LC50 value for Nile tilapia larvae was calculated to be 1.57 mg/l.
authors.affiliation: Faculty of Education, Department of Biology, University of Gazi, Teknikokullar, 06500 Ankara, Turkey. aligul@gazi.edu.tr
authors.forename: Ali
authors.initials: A
authors.lastname: Gül
mesh_terms: D000818:Animals; D004390:Chlorpyrifos / Q000031:analogs & derivatives* / Q000633:toxicity*; D023681:Cichlids / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D007306:Insecticides / Q000633:toxicity*; D007814:Larva / Q000187:drug effects / Q000378:metabolism; D007928:Lethal Dose 50; D009949:Orientation / Q000187:drug effects; D013997:Time Factors; D023382:Toxicity Tests, Acute
chemical_list: D007306:Insecticides; D004390:Chlorpyrifos; C007031:chlorpyrifos-methyl