Lethal and sublethal effects of three insecticides on two developmental stages of xenopus laevis and comparison with other amphibians

• Published in: Environmental toxicology and chemistry 2013-09, Vol.32 (9), p.2056-2064
• Main Authors: Yu, Shuangying, Wages, Mike R., Cai, Qingsong, Maul, Jonathan D., Cobb, George P.
• Format: Article
• Language: English
• Subjects: Amphibians; Animal, plant and microbial ecology; Animals; Anura - abnormalities; Anura - embryology; Anura - growth & development; Applied ecology; Biological and medical sciences; Chemicals; Comparative analysis; Comparative toxicity; Cypermethrin; Developmental stages; Ecotoxicology, biological effects of pollution; Effects of pollution and side effects of pesticides on vertebrates; Embryo, Nonmammalian - abnormalities; Embryo, Nonmammalian - drug effects; Embryo, Nonmammalian - physiology; Embryos; Endosulfan; Endosulfan - toxicity; Female; FETAX; Frogs; Fundamental and applied biological sciences. Psychology; Hydrocarbons, Chlorinated; Insecticides; Insecticides - toxicity; Larva - drug effects; Larva - physiology; Larvae; Malathion; Malathion - toxicity; Male; Median lethal concentration (LC50); Organic compounds; Organophosphorus compounds; Organophosphorus pesticides; Pesticides; Pyrethrins - toxicity; Pyrethroids; Reptilia. Amphibia; Risk assessment; Species Specificity; Sublethal effects; Teratogenesis; Toxicity; Water Pollutants - toxicity; Xenopus laevis - abnormalities; Xenopus laevis - embryology; Xenopus laevis - growth & development
• ISSN: 0730-7268; 1552-8618
• DOI: 10.1002/etc.2280

It has been suggested that Xenopus laevis is less sensitive than other amphibians to some chemicals, and therefore, that the Frog Embryo Teratogenesis Assay—Xenopus (FETAX) may have limited use in risk assessments for other amphibians. However, comparisons are based mostly on results of FETAX, which emphasizes embryos. Larval X. laevis may be more sensitive to chemicals than embryos and may serve as a better life stage in risk assessments. The present study was conducted to determine the lethal and sublethal effects of 3 insecticides (malathion, endosulfan, and α‐cypermethrin) on X. laevis embryos and larvae and to compare toxicity of X. laevis with that of other amphibians. All 3 insecticides have different modes of action, and they caused mortality, malformations, and growth inhibition in both developmental stages. Compared with embryos, larvae were more sensitive to endosulfan and α‐cypermethrin but not to malathion. Xenopus laevis larvae had low sensitivity to endosulfan, median sensitivity to malathion, and high sensitivity to α‐cypermethrin/cypermethrin relative to other larval amphibians. Our results suggest that X. laevis larvae may generate more protective toxicity estimates in risk assessments than embryos. Xenopus laevis may have limited use in evaluating risk of organochlorine insecticides to other amphibians but may provide useful toxicity thresholds for pyrethroid and perhaps organophosphorus insecticides. Environ Toxicol Chem 2013;32:2056–2064. © 2013 SETAC