Toxicity of carbamates to the brine shrimp Artemia salina and the effect of atropine, BW284c51, iso-OMPA and 2-PAM on carbaryl toxicity

The acute toxicity of aldicarb, carbaryl, propoxur and oxamyl to three age classes of Artemia salina was evaluated. There was an increase in toxicity of the four carbamates following longer development of A. salina. The effect of the pretreatment with the non-selective muscarinic antagonist, atropine, a highly specific reversible acetylcholinesterase inhibitor, BW284c51, an inhibitor of other serine-containing esterases, iso-OMPA and a cholinesterase-reactivating oxime, 2-PAM on carbaryl-induced lethality in the three age classes of A. salina was investigated. The lethal action of carbaryl was completely prevented by pretreatment of A. salina with atropine. Iso-OMPA when given in low concentrations (7.54–0.73 μmol/l) and BW284c51 (58.1–0.227 μmol/l) afforded a maximal protection about 75, 85 and 100% for A. salina 24-, 48- and 72-h old, respectively. In contrast, relatively higher concentrations of iso-OMPA pretreatment (65–1000 μmol/l) showed a potentiating effect of carbaryl toxicity. The acute effect of carbaryl was enhanced by 2-PAM. ©