title: Pyrene metabolism in the springtail Orchesella cincta L. (Collembola, Entomobryidae).
abstract: A novel, solvent-free spiking method was used to contaminate foodstuff (Desmococcus spp. algae) with pyrene for bioassays with the springtail Orchesella cincta L. (Collembola, Entomobryidae). The primary metabolite 1-hydroxypyrene and two conjugates (pyrene-1-glucoside and one tentatively identified as pyrene-1-glucosidemalonate) were quantified in the insects by high-performance liquid chromatography (HPLC) with fluorescence detection. Individuals from an unpolluted site (SUS population) were capable of rapid metabolism of pyrene, reaching an apparent steady state after 24 h with a composite assimilation/transformation rate of approximately 25 pmol pyrene x g(-1) fresh weight x h(-1) at an exposure level of approximately 18 microg pyrene x g(-1) dry weight algae. A cadmium (Cd)-tolerant population (TOL), genetically distinct from SUS, was exposed in parallel and the populations' pyrene metabolism compared in order to gain insight into any potential cost of Cd-tolerance. The TOL animals assimilated and/or performed phase 1 transformation of pyrene approximately twice as fast as SUS (approximately 56 pmol x g(-1) x h(-1)), but there was no significant difference in the elimination rate constants between SUS and TOL animals. Attributing this difference to any specific cost of Cd-tolerance requires more work and may he coincidental to metal tolerance, but pyrene metabolism in these distinct genotypes, subjected to different selection pressures, was nevertheless significantly different.
authors.affiliation: Institute of Ecological Science, Department of Animal Ecology, Vrije Universiteit, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands. mhoqam@iiqab.csic.es
authors.forename: Mike
authors.initials: M
authors.lastname: Howsam
authors.forename: Nico M
authors.initials: NM
authors.lastname: Van Straalen
mesh_terms: D000222:Adaptation, Physiological; D000818:Animals; D002104:Cadmium / Q000494:pharmacology*; D004785:Environmental Pollutants / Q000494:pharmacology*; D005456:Fluorescent Dyes / Q000378:metabolism*; D005838:Genotype; D007313:Insecta / Q000235:genetics / Q000502:physiology*; D011084:Polycyclic Aromatic Hydrocarbons / Q000378:metabolism*; D011721:Pyrenes / Q000378:metabolism*; D018570:Risk Assessment
chemical_list: D004785:Environmental Pollutants; D005456:Fluorescent Dyes; D011084:Polycyclic Aromatic Hydrocarbons; D011721:Pyrenes; D002104:Cadmium; C030984:pyrene