Toxicity of Piperonyl Butoxide — Carbaryl Synergism on the Snail Lymnaea acuminata

Abstract Effects of piperonyl butoxide and carbaryl synergism were studied on the metabolism of the snail Lymnaea acuminata. Snails were exposed to 40 % and 80 % of the 48 h LC50 of carbaryl or carbaryl + piperonyl butoxide mixture (1:5). The amount of carbaryl present in the LC50 mixture was only 0.23 % of the LC50 of carbaryl alone. The treatments caused a dose‐dependent decrease in glycogen and protein levels and acetylcholinesterase (AChE) and alkaline phosphatase activity; simultaneously, there was an increase in levels of lactic acid, reducing sugars and amino acid and the activity of acid phosphatase. Significant differences in AChE and phosphatase activity were also observed between the effects of equivalent concentrations of carbaryl and carbaryl‐synergist.