title: Biochemical and morphological responses in Chironomus riparius (Diptera, Chironomidae) larvae exposed to lead-spiked sediment.
abstract: The aim of the present study was to assess the potential use of biochemical markers and mentum deformities as indicators of long-term exposure to lead (Pb) in Chironomus riparius larvae. To do this, the authors measured 3 biochemical markers (i.e., malondialdehyde level, metallothionein concentration, and energy reserve content) as well as larval growth and mentum deformities after 16-d exposure to sediment containing Pb. The concentrations studied ranged from 3.5 mg/kg to 505.5 mg/kg dry weight. Despite the bioaccumulation of Pb in C. riparius bodies, frequencies of both mentum deformities and the dry weight were not significantly different between the control and stressed groups. On the contrary, Pb exposure caused a significant increase of both malondialdehyde level and metallothionein concentration. The increase of body Pb concentrations did not significantly modify body copper and zinc concentrations. Moreover, we observed a decrease of total lipid content and an increase of glycogen content as a function of a dose-response relationship, while no variation in protein concentrations was observed. Despite the adverse effects observed at the biochemical level, larval development was not affected. These results suggested that measurements of malondialdehyde level, metallothionein concentration, and energy reserve content can be used as relevant biomarkers of long-term sublethal exposure to Pb in C. riparius larvae.
authors.affiliation: Centre d'Etude Technique de l'Equipement d'Ile de France, Département Ville Durable, Trappes, France.
authors.forename: Helene
authors.initials: H
authors.lastname: Arambourou
authors.forename: Eric
authors.initials: E
authors.lastname: Gismondi
authors.forename: Philippe
authors.initials: P
authors.lastname: Branchu
authors.forename: Jean-Nicolas
authors.initials: JN
authors.lastname: Beisel
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D002683:Chironomidae / Q000033:anatomy & histology / Q000187:drug effects* / Q000378:metabolism; D003300:Copper / Q000378:metabolism; D019015:Geologic Sediments / Q000737:chemistry*; D007814:Larva / Q000033:anatomy & histology / Q000187:drug effects / Q000378:metabolism; D007854:Lead / Q000032:analysis / Q000633:toxicity*; D008315:Malondialdehyde / Q000378:metabolism; D008668:Metallothionein / Q000378:metabolism; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000633:toxicity*; D015032:Zinc / Q000378:metabolism
chemical_list: D015415:Biomarkers; D014874:Water Pollutants, Chemical; D007854:Lead; D008315:Malondialdehyde; D003300:Copper; D008668:Metallothionein; D015032:Zinc
keywords: Biochemical marker; Chironomus riparius; Energy reserve content; Lead; Mentum deformity