The integrated biomarker response in three anuran species larvae at sublethal concentrations of cypermethrin, chlorpyrifos, glyphosate, and glufosinate-ammonium

Abstract

The aim of the present study was to evaluate the response in larvae of the anuran species Rhinella arenarum, Rhinella dorbignyi and Odontophrynus americanus exposed to glyphosate (GLY, 2.5mg L -1 ), cypermethrin (CYP, 0.013mg L -1 ), chlorpyrifos (CP, 0.1mg L -1 ) and glufosinate-ammonium (GLU, 15mg L -1 ) using two behavioral endpoints: mean speed (MS) and total distance moved (TD); and two enzymatic biomarkers: acetylcholinesterase (AChE) and butyrylcholinesterase (BChE).In order to assess a global response and to determine the most sensitive species, an integrated biomarker response (IBR) index was calculated. Behavioral biomarkers were tested at 1 and 60 min, and the enzymes at 60 min after exposure. The results showed that: (1) there were statistical differences between species in a series of responses in swimming behavior, and cholinesterase activities within the first-hour of exposure to CYP, GLY, and CP at environmentally relevant concentrations (ERC);(2) IBR determined that Rhinella species were the most sensitive of the species tested and(3) IBR provided a comprehensive assessment of the health status of species exposed to ERC of a wide variety of agrochemicals globally and frequently used.