title: Impact of guthion on survival and growth of the frog Pseudacris regilla and the salamanders Ambystoma gracile and Ambystoma maculatum.
abstract: The effects of the insecticides Guthion (technical grade) and Guthion 2S (commercial formulation) on survival and growth of tadpoles of the Pacific treefrog Pseudacris regilla, and larvae of the Northwestern salamander Ambystoma gracile and the spotted salamander Ambystoma maculatum were determined in continuous-flow exposures in the laboratory. Ninety-six-hour LC50 values were >3.6 mg/L for P. regilla with technical grade Guthion and 1.47 mg/L with the formulation Guthion 2S (measured as active ingredient Guthion). Ten-day LOAEL and NOAEL values based on length and weight for P. regilla with Guthion were 3.60 and 0.98 mg/L. LOAEL and NOAEL values based on length and weight for P. regilla with Guthion 2S were 0.17 and 0.07 mg/L. The 96-h LC50 for Guthion 2S was 1.67 and 1.90 mg/L for A. gracile and A. maculatum, respectively. LOAEL and NOAEL values based on length and weight for A. gracile with Guthion 2S were 0.22 and 0.10 mg/L; they were 0.11 and 0.03 mg/L for A. maculatum based on weight. These species are as similar in sensitivity as some fish species but are more tolerant to Guthion than most invertebrates.
authors.affiliation: U.S. Environmental Protection Agency, National Health and Ecological Effects Research Laboratory, Western Ecology Division, 200 SW 35th Street, Corvallis, Oregon 97333, USA.
authors.forename: A V
authors.initials: AV
authors.lastname: Nebeker
authors.forename: G S
authors.initials: GS
authors.lastname: Schuytema
authors.forename: W L
authors.initials: WL
authors.lastname: Griffis
authors.forename: A
authors.initials: A
authors.lastname: Cataldo
mesh_terms: D000557:Ambystoma / Q000254:growth & development*; D000818:Animals; D001001:Anura / Q000254:growth & development*; D001387:Azinphosmethyl / Q000633:toxicity*; D007306:Insecticides / Q000633:toxicity; D007814:Larva / Q000187:drug effects / Q000254:growth & development; D013534:Survival; D014874:Water Pollutants, Chemical / Q000633:toxicity
chemical_list: D007306:Insecticides; D014874:Water Pollutants, Chemical; D001387:Azinphosmethyl