Elucidating pesticide sensitivity of two endogeic earthworm species through the interplay between esterases and glutathione S-transferases

Earthworms are common organisms in soil toxicity-testing framework, and endogeic species currently recommended due to their ecological role agroecosystem. However, little is known on pesticide metabolic capacities. We firstly compared the baseline activity of B-esterases glutathione-S-transferase Allolobophora chlorotica Aporrectodea caliginosa. Secondly, vulnerability these exposure was assessed by vitro trials using organophosphate (OP) chlorpyrifos-ethyl-oxon (CPOx) ethyl-paraoxon (POx), short-term (7 days) vivo responses contaminated with pesticides. Among B-esterases, acetylcholinesterase (AChE) abundant microsomal fraction (80% 70% total for A. caliginosa chlorotica, respectively). Carboxylesterase (CbE) activities were measured three substrates examine differences isoenzyme sensitivity both exposure. CbEs mainly found cytosolic 60% GST exclusively soluble species. Both OPs inhibited a concentration-dependent manner. In revealed pesticide-specific response, being AChE more sensitive CPOx POx. CbE at same extent The 7-d showed less OPs, which contrasted outcomes from experiments. This non-related functional between approaches assessing toxicity suggests that other mechanisms linked OP bioactivation excretion could have significant earthworms.