Chlorpyrifos-Induced Toxicity in Duttaphrynus melanostictus (Schneider 1799) Larvae

• Published in: Archives of environmental contamination and toxicology 2011-05, Vol.60 (4), p.690-696
• Main Authors: Wijesinghe, M. R., Bandara, M. G. D. K., Ratnasooriya, W. D., Lakraj, G. P.
• Format: Article
• Language: English
• Subjects: Agricultural chemicals; Agricultural land; Agrochemicals; Amphibia; Amphibians; Analysis; Animal, plant and microbial ecology; Animals; Applied ecology; Asian; Biological and medical sciences; Bufonidae; Chlorpyrifos; Chlorpyrifos - toxicity; Delay; Dose-Response Relationship, Drug; Drinking water; Earth and Environmental Science; Ecotoxicology; Ecotoxicology, biological effects of pollution; Environment; Environmental Chemistry; Environmental Health; Environmental Monitoring; Experiments; Fundamental and applied biological sciences. Psychology; General aspects; Impairment; Landscapes; Larva - drug effects; Larva - growth & development; Larvae; Lethal Dose 50; Metamorphosis; Metamorphosis, Biological - drug effects; Monitoring/Environmental Analysis; Mortality; Organophosphates; Organophosphorus pesticides; Pesticides; Pollution; Reptiles & amphibians; Risk; Soil Science & Conservation; Sri Lanka; Studies; Swimming; Toads; Toxicity; Variance analysis; Water Pollutants, Chemical - toxicity; Water temperature; Zoology
• ISSN: 0090-4341; 1432-0703
• DOI: 10.1007/s00244-010-9577-3

This study investigates the effects of continuous exposure to a widely used organophosphate pesticide, chlorpyrifos, on survival, growth, development, and activity of larvae of the Asian common toad, Duttaphrynus melanostictus Schneider 1799. Larvae were continuously exposed to six different concentrations (1–1,500 μg l −1 ) of commercial-grade chlorpyrifos for 14 days and monitored for 1 additional week. Chlorpyrifos at ≥1,000 μg l −1 caused significantly high and dose-dependent mortality, and the weekly LC50 7 day–21 day values ranged from 3,003 to 462 μg l −1 . Larvae surviving exposure to ≥500 μg l −1 chlorpyrifos showed significant growth impairment, delays in metamorphosis, and decreased swimming activity. Tail abnormalities were the most common morphologic deformity at concentrations of 1,000 and 1,500 μg l −1 chlorpyrifos. The findings of the present study highlight the need to recognize the potential risk that agrochemicals pose to amphibians inhabiting agricultural landscapes in Sri Lanka and other Asian countries.