title: Avoidance response of rainbow trout Oncorhynchus mykiss to hexavalent chromium solutions.
abstract: Laboratory tests were conducted on one-year-old rainbow trout Oncorhynchus mykiss to evaluate their ability to detect and avoid hexavalent chromium (Cr(6+)). Test fish were given a choice to discriminate between clean water and Cr(6+) solutions of six sublethal concentrations ranging from 0.0015 to 0.3 mg Cr/L in a counter-current flow, steep gradient chamber. The intensity of avoidance response reached a significant level at test concentrations of 0.003 mg Cr/L and higher, and was directly proportional to the Cr(6+) concentration logarithm. Avoidance threshold was estimated through regression analysis and to be 0.0017 mg Cr/L. This result is approximately sixfold lower than maximum-permitted concentration of 0.01 mg Cr/L accepted as the Lithuanian water-quality guideline for the protection of aquatic life.
authors.affiliation: Laboratory of Hydrobiont Ecology and Physiology, Institute of Ecology of Vilnius University, Akademijos 2, 08412 Vilnius-21, Lithuania. Gintaras.Svecevicius@takas.lt
authors.forename: Gintaras
authors.initials: G
authors.lastname: Svecevicius
mesh_terms: D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects*; D002857:Chromium / Q000633:toxicity*; D004305:Dose-Response Relationship, Drug; D017686:Oncorhynchus mykiss / Q000502:physiology*; D012996:Solutions; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D012996:Solutions; D014874:Water Pollutants, Chemical; D002857:Chromium; C074702:chromium hexavalent ion