Relationship of cholinesterase activity inhibition and effects at higher levels of biological organization in Chironomus xanthus (Chironomidae, Diptera) exposed to parathion

• Grant number: 06/04392-7
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: November 01, 2006
• End date: October 31, 2007
• Field of knowledge: Biological Sciences - Ecology - Applied Ecology
• Principal Investigator: Liane Biehl Printes
• Grantee: Gisela Natacha Cazela
• Host Institution: Escola de Engenharia de São Carlos (EESC). Universidade de São Paulo (USP). São Carlos , SP, Brazil

Abstract

The use of biochemical biomarkers as assessment tools has shown potential in environmental studies. Inhibition of cholinesterase (ChE) activity due to exposure to organophosphate and carbamate insecticides, as well as metals, is a well-known marker to detect the presence of these contaminants in the environment. However, to validate the utilisation of this tool in environmental assessment programmes it is still necessary to establish relationships between ChE activity and toxic effects at higher levels of biological organization; this is even more crucial in terms of aquatic invertebrates. Hence, this research aims to evaluate the relationships between ChE inhibition and toxic effect at the individual level (survival, dry-weight and adult emergence) in larvae of Chironomus xanthus exposed to the organophosphorus parathion and the non-essential metal cadmium (isolated and in combination). Therefore, this research will contribute to the “state of the art” of the use of biomarkers in environmental assessment programmes. In addition, our findings will directly contribute the development of Ecotoxicology in Brazil, since this work will be performed with a native species adapted to the local conditions.