No acute toxicity to Uca pugnax, the mud fiddler crab, following a 96-h exposure to sediment-bound permethrin.
In coastal areas, the application of pyrethroid insecticides and the resulting sediment residues pose a potential threat to marine benthic ecosystems. Pyrethroids cause acute toxicity and exhibit a wide range of sublethal effects on fish and crustaceans when exposure is aqueous. Fiddler crabs that inhabit salt marsh sediment are sensitive to sediment-associated pollutants and serve as a sentinel species for xenobiotic exposure. We exposed adult U. pugnax to salt marsh sediment spiked with different 60% trans/40% cis permethrin concentrations for 96 h, and evaluated changes in oxygen consumption rate, hemolymph osmolarity, and glutathione S-transferase activity (GST) following exposure. Marsh sediment was not lethal to U. pugnax at permethrin concentrations of 100-10,000 microg/kg. Sediment-bound permethrin had no significant effect on respiration and osmoregulation. Exposure caused an induction of hepatopancreas GST in a dose-dependent manner. Gill and midgut tissues showed induction at permethrin concentrations at 10,000 microg/kg. We conclude that short term exposure to permethrin-contaminated sediment does not pose a significant threat to this species or impact respiration and osmoregulation. Furthermore, increased GST activity allows us to evaluate this enzyme's induction as a generalist biomarker for sediment-bound pyrethroid exposures.
Stueckle
Todd A
TA
Department of Biology, West Virginia University, PO Box 6057, Morgantown, West Virginia, USA. tstueckl@mix.wvu.edu
Griffin
Kristin
K
Foran
Christy M
CM
D000818:Animals; D003386:Brachyura / Q000187:drug effects* / Q000201:enzymology; D004305:Dose-Response Relationship, Drug; D041981:Gastrointestinal Tract / Q000201:enzymology; D019015:Geologic Sediments / Q000737:chemistry*; D005880:Gills / Q000201:enzymology; D005982:Glutathione Transferase / Q000378:metabolism; D043143:Hepatopancreas / Q000201:enzymology; D007306:Insecticides / Q000737:chemistry / Q000633:toxicity; D010101:Oxygen Consumption; D026023:Permethrin / Q000737:chemistry* / Q000633:toxicity*; D013997:Time Factors; D014867:Water / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000633:toxicity; D014882:Water-Electrolyte Balance
D007306:Insecticides; D014874:Water Pollutants, Chemical; D014867:Water; D026023:Permethrin; D005982:Glutathione Transferase