title: Organic carbon content effects on bioavailability of pyrethroid insecticides and validation of solid phase extraction with Poly (2,6-diphenyl-p-phenylene oxide) Polymer by Daphnia magna toxicity tests.
abstract: Solid phase extraction with Poly (2,6-diphenyl-p-phenylene oxide) Polymer (Tenax) was used for determining the bioavailability of eleven pyrethroids in field collected sediments with different organic carbon content (OC). The bioavailable fraction of pyrethroids decreased with increasing OC in sediments; the percentages of desorption ranged from 10 to 20% for sediment with higher OC content (5.8%) and 15-40% for that with lower OC (2%). Generally pyrethroids showed low bioavailability and cyfluthrin resulted to be the most bioavailable among the studied pyrethroids. Acute toxicity tests with Daphnia magna were carried out on sediment spiked with three selected pyrethroids (λ-cyhalothrin, cypermethrin and deltamethrin) and served to validate the efficiency of Tenax as a method for assessing the bioavailability of pyrethroids. Toxicity test demonstrated that Tenax was able to remove the toxic bio-available fraction of pyrethroids in sediment. Extracts from Tenax beads after the desorption experiments and spiked sediment before desorption had an equivalent toxicity (LC50) to D. magna neonates at 48 and 72 h of exposure. These results indicate that Tenax beds can be used to predict bio-available and toxic fractions of pyrethroids sorbed to sediments to aquatic organisms like D. magna.
authors.affiliation: Institute of Environmental Assessment and Water Research (IDAEA-CSIC), Jordi Girona 18, 08034 Barcelona, Spain.
authors.forename: M L
authors.initials: ML
authors.lastname: Feo
authors.forename: C
authors.initials: C
authors.lastname: Corcellas
authors.forename: C
authors.initials: C
authors.lastname: Barata
authors.forename: A
authors.initials: A
authors.lastname: Ginebreda
authors.forename: E
authors.initials: E
authors.lastname: Eljarrat
authors.forename: D
authors.initials: D
authors.lastname: Barceló
mesh_terms: D000327:Adsorption; D000818:Animals; D003621:Daphnia / Q000187:drug effects; D008401:Gas Chromatography-Mass Spectrometry; D019015:Geologic Sediments / Q000737:chemistry*; D006812:Humic Substances / Q000032:analysis*; D007306:Insecticides / Q000032:analysis* / Q000633:toxicity; D011108:Polymers / Q000737:chemistry*; D011722:Pyrethrins / Q000032:analysis* / Q000633:toxicity; D015203:Reproducibility of Results; D052616:Solid Phase Extraction; D053719:Tandem Mass Spectrometry; D023382:Toxicity Tests, Acute; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000633:toxicity
chemical_list: D006812:Humic Substances; D007306:Insecticides; D011108:Polymers; D011722:Pyrethrins; D014874:Water Pollutants, Chemical; C010514:tenax