title: Rapid loss of lampricide from catfish and rainbow trout following routine treatment.
abstract: Rainbow trout (Oncorhynchus mykiss) and channel catfish (Ictalurus punctatus) were exposed to 3-trifluoromethyl-4-nitrophenol (TFM) and Bayluscide (niclosamide) during a sea lamprey control treatment of the Ford River, located in the upper peninsula of Michigan. Caged fish were exposed to a nominal concentration of 0.02 mg/L of niclosamide for a period of approximately 12 h. Samples of fillet tissue were collected from each fish species before treatment and at 6, 12, 18, 24, 48, 96, and 192 h following the arrival of the block of chemical at the exposure site. The fish were dissected, homogenized, extracted, and analyzed by high-performance liquid chromatography. The major residues found in the fillet tissues were TFM and niclosamide. Niclosamide concentrations were highest 12 h after arrival of the chemical block for rainbow trout (0.0395 +/- 0.0251 microg/g) and 18 h after arrival of the chemical block for channel catfish (0.0465 +/- 0.0212 microg/g). Residues decreased rapidly after the block of lampricide had passed and were below the detection limits in fillets of rainbow trout within 24 h and channel catfish within 96 h after the arrival of the lampricide.
authors.affiliation: Upper Midwest Environmental Sciences Center, Biological Resources Division, U.S. Geological Survey, 2630 Fanta Reed Road, La Crosse, Wisconsin 54603, USA. vcdawson@aol.com
authors.forename: Verdel K
authors.initials: VK
authors.lastname: Dawson
authors.forename: Theresa M
authors.initials: TM
authors.lastname: Schreier
authors.forename: Mike A
authors.initials: MA
authors.lastname: Boogaard
authors.forename: Nancy J
authors.initials: NJ
authors.lastname: Spanjers
authors.forename: William H
authors.initials: WH
authors.lastname: Gingerich
mesh_terms: D000818:Animals; D002851:Chromatography, High Pressure Liquid; D007059:Ictaluridae / Q000378:metabolism*; D007798:Lampreys; D008824:Michigan; D009534:Niclosamide / Q000032:analysis / Q000493:pharmacokinetics*; D009596:Nitrophenols / Q000032:analysis / Q000493:pharmacokinetics*; D017686:Oncorhynchus mykiss / Q000378:metabolism*; D010571:Pest Control; D010573:Pesticide Residues / Q000032:analysis; D010575:Pesticides / Q000493:pharmacokinetics*; D014020:Tissue Extracts / Q000737:chemistry
chemical_list: D009596:Nitrophenols; D010573:Pesticide Residues; D010575:Pesticides; D014020:Tissue Extracts; D009534:Niclosamide; C003687:3-trifluoromethyl-4-nitrophenol