title: Life cycle responses of the midge Chironomus riparius to polycyclic aromatic compound exposure.
abstract: During acute exposure, polycyclic aromatic compounds (PACs) act mainly by narcosis, but during chronic exposure the same compounds may exert sublethal life cycle effects. The aim of this study was therefore to evaluate the chronic effects of sediment spiked PACs on the emergence of the midge Chironomus riparius. Three isomer pairs were selected, and 28-day LC50 values and 50% emergence times (EMt50) were determined. Concentration-response relationships were observed for phenanthrene, acridine, phenanthridine and acridone. Anthracene and phenanthridone had no effect on total emergence, but did cause a delay in emergence. Calculated porewater LC50 values correlated well with logKow values, suggesting narcosis as mode of action. In contrast, effect concentrations for delay in emergence (EMt50) deviated from narcosis, suggesting a specific mode of action during chronic exposure. It is concluded that emergence is a powerful endpoint to detect life cycle effects of PACs on a key sediment inhabiting invertebrate.
authors.affiliation: Department of Aquatic Ecology and Ecotoxicology, Institute of Biodiversity and Ecosystem Dynamics, University of Amsterdam, Kruislaan 320, 1098 SM Amsterdam, the Netherlands. mleon@science.uva.nl
authors.forename: Miriam León
authors.initials: ML
authors.lastname: Paumen
authors.forename: Eefje
authors.initials: E
authors.lastname: Borgman
authors.forename: Michiel H S
authors.initials: MH
authors.lastname: Kraak
authors.forename: Cornelis A M
authors.initials: CA
authors.lastname: van Gestel
authors.forename: Wim
authors.initials: W
authors.lastname: Admiraal
mesh_terms: D000818:Animals; D002683:Chironomidae / Q000187:drug effects / Q000254:growth & development*; D004784:Environmental Monitoring / Q000379:methods; D019015:Geologic Sediments; D007814:Larva; D008018:Life Cycle Stages; D011084:Polycyclic Aromatic Hydrocarbons / Q000633:toxicity*; D012989:Soil Pollutants / Q000633:toxicity*; D036401:Toxicity Tests, Chronic
chemical_list: D011084:Polycyclic Aromatic Hydrocarbons; D012989:Soil Pollutants