Acute toxicity of chlorpyrifos to the non-target organism Cnesterodon decemmaculatus

Abstract

Chlorpyrifos is the most used insecticide in Argentina. Cnesterodon decemmaculatus is a widely distributed, endemic fish from Neotropical America. It attains high densities in the shallow water assemblages of Argentina and Brazil. The aim of this study was to assess the acute toxicity of chlorpyrifos to C. decemmaculatus. The mean 96-h LC₅₀ of three independent determinations was 105.3 (± 3.1) μg/L. Sublethal effects were observed. Swimming behavioral changes at each chlorpyrifos exposure concentration were reported. C. decemmaculatus represents a good model for ecotoxicological risk assessment.

Keywords:

• acute toxicity
• insecticide
• fish
• Cnesterodon decemmaculatus

Acknowledgments

The authors thank the reviewers and the editor for their valuable comments, and Lisa Hunt for assistance with language. This research was supported by grants from the Argentine National Scientific and Technical Research Council (CONICET) [PIP 2011 #0180], and the Argentine National Agency for Scientific and Technological Promotion (ANPCyT) [PICT 2010 #0446].