title: Studies on lethal concentrations and toxicity stress of some xenobiotics on aquatic organisms.
abstract: Three widely used xenobiotics pentachlorophenol (PCP), 2,4-dichlorophenoxyacetic acid (2,4-D) and 2-chloro-2,6-diethyl-N-(butoxymethyl) acetanilide (Butachlor) are evaluated for acute toxicity and stress behavior on freshwater fish (Heteropneustes fossilis, Clarias batrachus, Channa punctatus) and mosquito larvae (Culex pipiens fatigans). The experiment was carried out by medium treatment using intermittent flow-through system. Median lethal concentrations (LC50) were calculated by probit analysis. The LC50 values and 95% confidence intervals showed variable range for tested chemicals. Mosquito larvae generally appeared resistant than fish, while H. fossilis was found to be most sensitive. Stress signs in the form of behavioral changes are also observed. Both types of organisms are recommended as good bioindicator for the risk assessment of aquatic environment due to chemicals tested.
authors.affiliation: Gene-Tox Laboratory, Division of Genetics, Department of Zoology, Aligarh Muslim University, Aligarh 202002, UP, India.
authors.forename: M Abul
authors.initials: MA
authors.lastname: Farah
authors.forename: Bushra
authors.initials: B
authors.lastname: Ateeq
authors.forename: M Niamat
authors.initials: MN
authors.lastname: Ali
authors.forename: Rubina
authors.initials: R
authors.lastname: Sabir
authors.forename: Waseem
authors.initials: W
authors.lastname: Ahmad
mesh_terms: D015084:2,4-Dichlorophenoxyacetic Acid / Q000633:toxicity; D000083:Acetanilides / Q000633:toxicity; D000818:Animals; D003465:Culex / Q000187:drug effects* / Q000378:metabolism; D005399:Fishes / Q000378:metabolism*; D007194:India; D007814:Larva / Q000187:drug effects / Q000378:metabolism; D007928:Lethal Dose 50; D010416:Pentachlorophenol / Q000633:toxicity; D010829:Physiological Phenomena / Q000187:drug effects*; D023382:Toxicity Tests, Acute; D015262:Xenobiotics / Q000633:toxicity*
chemical_list: D000083:Acetanilides; D015262:Xenobiotics; D015084:2,4-Dichlorophenoxyacetic Acid; C054409:butachlor; D010416:Pentachlorophenol