title: Bioavailability and biotransformation of sediment-associated pyrethroid insecticides in Lumbriculus variegatus.
abstract: In the present study, bioaccumulation potential of two pyrethroid insecticides, bifenthrin and permethrin, was measured using a Lumbriculus variegatus sediment bioaccumulation test. Two sediments differing in their physical characteristics and two different aging periods were tested. Desorption rates measured by Tenax extraction suggested that pyrethroids were bioavailable to L. variegatus, however bioavailability varied among chemicals, sediments and aging time, and was greater for permethrin than bifenthrin. The relatively low biota-sediment accumulation factor (BSAF) values resulted from the extensive biotransformation of pyrethroids by L. variegatus. Biotransformation capacity of L. variegatus to permethrin was further studied with a water-only exposure, and the percentage parent compound dropped to 36.0% after 14 d. These results indicated sediment-associated pyrethroids were bioavailable to L. variegatus, however bioaccumulation was limited because L. variegatus was capable of biotransforming the pyrethroids.
authors.affiliation: State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
authors.forename: Jing
authors.initials: J
authors.lastname: You
authors.forename: Amanda
authors.initials: A
authors.lastname: Brennan
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Lydy
mesh_terms: D000818:Animals; D001682:Biological Availability; D001711:Biotransformation; D019015:Geologic Sediments / Q000737:chemistry*; D009835:Oligochaeta / Q000378:metabolism*; D026023:Permethrin / Q000737:chemistry / Q000378:metabolism; D010573:Pesticide Residues / Q000737:chemistry / Q000378:metabolism*; D011722:Pyrethrins / Q000737:chemistry / Q000378:metabolism*; D012989:Soil Pollutants / Q000737:chemistry / Q000378:metabolism*
chemical_list: D010573:Pesticide Residues; D011722:Pyrethrins; D012989:Soil Pollutants; D026023:Permethrin; C099952:bifenthrin