title: Acute and chronic life cycle toxicity of acenaphthene and 2,4,6-trichlorophenol to the midge Paratanytarsus parthenogeneticus (Diptera: Chironomidae).
abstract: The acute and life cycle toxicities of acenaphthene and 2,4,6-trichlorophenol (2,4,6-TCP) were evaluated using the parthenogenic dipteran larva, Paratanytarsus parthenogeneticus, of the family Chironomidae. Static 48 h acute toxicity tests employed third instar larvae, and the flow-through 20-day life cycle tests were initiated with eggs. No acute lethal effect was observed in the saturated concentration (2.1 mg/l) of acenaphthene in water, and the median lethal concentration of 2,4,6-TCP was approximately 40 mg/l. In the life cycle toxicity test with acenaphthene, hatchability of the midge was affected by 50% at an exposure concentration of approximately 0.17 mg/l. The median effective concentration for larval, pupal and adult development was found between 0.06 and 0.07 mg/l, respectively, and these were significantly lower than the effective concentration for hatching success. With regard to 2,4,6-TCP toxicity, the median effective concentration for midge hatchability was 4.23 mg/l. The larval development, pupal formation and adult emergence, however were impeded at 1.60, 1.46 and 1.33 mg/l, respectively. Each level was noticeably lower than the median effective concentration for hatchability. The concentrations for each compound that interfered with the development to fourth instar, pupa and adult were not significantly different. These results indicate that larval developments after hatching were the most sensitive stages and affected the success of midge growth.
authors.affiliation: Department of Environmental Health Sciences, School of Public Health, The University of Michigan, Ann Arbor 48109-2029, USA. pgmeier@sph.umich.edu
authors.forename: P G
authors.initials: PG
authors.lastname: Meier
authors.forename: K
authors.initials: K
authors.lastname: Choi
authors.forename: L I
authors.initials: LI
authors.lastname: Sweet
mesh_terms: D000073:Acenaphthenes / Q000032:analysis / Q000633:toxicity*; D000818:Animals; D002683:Chironomidae / Q000502:physiology*; D002733:Chlorophenols / Q000032:analysis / Q000633:toxicity*; D007814:Larva / Q000254:growth & development / Q000502:physiology; D008018:Life Cycle Stages / Q000187:drug effects*; D012098:Reproduction / Q000187:drug effects; D013997:Time Factors; D014881:Water Supply / Q000032:analysis
chemical_list: D000073:Acenaphthenes; D002733:Chlorophenols; C024564:2,4,6-trichlorophenol; C042552:acenaphthene