title: Joint effects of pesticides and ultraviolet-B radiation on amphibian larvae.
abstract: A combination of multiple stressors may be linked to global amphibian declines. Of these, pesticides and UVB radiation co-exposures were examined on the African clawed frog (Xenopus laevis) to provide information that may be useful for amphibian conservation. The independent action model and inferential statistics were used to examine interactions between pesticides (malathion, endosulfan, α-cypermethrin, or chlorothalonil) and environmentally relevant UVB exposures. UVB radiation alone caused 35-68% mortality and nearly 100% of malformations. Pesticides and UVB had additive effects on larval mortality; however, several non-additive effects (antagonistic and synergistic interactions) were observed for total body length. Insecticides mainly affected axial development, whereas UVB radiation caused high incidence of edema, gut malformations, and abnormal tail tips. These results suggest that sublethal developmental endpoints were more sensitive for detecting joint effects. This work has implications for amphibian risk assessments for ecosystems where pesticides and high UVB radiation may co-occur.
authors.affiliation: Department of Environmental Toxicology, Texas Tech University, Lubbock, TX 79416, USA.
authors.forename: Shuangying
authors.initials: S
authors.lastname: Yu
authors.affiliation: Department of Environmental Toxicology, Texas Tech University, Lubbock, TX 79416, USA.
authors.forename: Mike
authors.initials: M
authors.lastname: Wages
authors.affiliation: Department of Environmental Toxicology, Texas Tech University, Lubbock, TX 79416, USA.
authors.forename: Morgan
authors.initials: M
authors.lastname: Willming
authors.affiliation: Department of Environmental Science, Baylor University, Waco, TX 76798, USA.
authors.forename: George P
authors.initials: GP
authors.lastname: Cobb
authors.affiliation: Department of Environmental Toxicology, Texas Tech University, Lubbock, TX 79416, USA. Electronic address: jmaul5@gmail.com.
authors.forename: Jonathan D
authors.initials: JD
authors.lastname: Maul
mesh_terms: D000014:Abnormalities, Drug-Induced; D000016:Abnormalities, Radiation-Induced; D000818:Animals; D004726:Endosulfan / Q000633:toxicity; D004781:Environmental Exposure / Q000009:adverse effects; D007306:Insecticides / Q000633:toxicity; D007814:Larva / Q000187:drug effects / Q000528:radiation effects; D008294:Malathion / Q000633:toxicity; D009570:Nitriles / Q000633:toxicity; D010575:Pesticides / Q000633:toxicity*; D011722:Pyrethrins / Q000633:toxicity; D018675:Toxicity Tests; D014466:Ultraviolet Rays / Q000009:adverse effects*; D014982:Xenopus laevis
chemical_list: D007306:Insecticides; D009570:Nitriles; D010575:Pesticides; D011722:Pyrethrins; C017160:cypermethrin; C005806:tetrachloroisophthalonitrile; D004726:Endosulfan; D008294:Malathion
keywords: Fungicide; Global climate change; Insecticide; Interaction; Xenopus laevis