title: Acute toxicity of peracetic acid (PAA) formulations to Ichthyophthirius multifiliis theronts.
abstract: Peracetic acid (PAA) is an antimicrobial disinfectant used in agriculture, food processing, and medical facilities. It has recently been suggested as a means to control infestations of Ichthyophthirius multifiliis. The purpose of this study was to determine the acute toxicity of two products containing 4.5% and 40% PAA to I. multifiliis theronts from two geographically separate isolates. Theronts were exposed to concentrations of PAA in 96-well plates containing groundwater at 23 degrees C. Acute toxicity was observed over a 4-h period. No significant difference in the median lethal concentration (LC(50)) estimates was evident between the two isolates at 4 h with the 4.5% PAA product (0.146 versus 0.108 mg/l PAA), while there was a statistical difference between the 4 h LC(50) with the 40% PAA product (0.274 versus 0.158 mg/l PAA). These results suggest that PAA is toxic to I. multifiliis theronts at low concentrations and that one of the isolates was more resistant to this compound.
authors.affiliation: USDA, Agricultural Research Service, Harry K. Dupree-Stuttgart National Aquaculture Research Center, P.O. Box 1050, Stuttgart, AR 72160, USA. Dave.Straus@ars.usda.gov
authors.forename: David L
authors.initials: DL
authors.lastname: Straus
authors.forename: Thomas
authors.initials: T
authors.lastname: Meinelt
mesh_terms: D000818:Animals; D000981:Antiprotozoal Agents / Q000494:pharmacology*; D002470:Cell Survival; D005399:Fishes / Q000469:parasitology; D016803:Hymenostomatida / Q000187:drug effects* / Q000302:isolation & purification; D007928:Lethal Dose 50; D010463:Peracetic Acid / Q000494:pharmacology*
chemical_list: D000981:Antiprotozoal Agents; D010463:Peracetic Acid