Methomyl is a carbamate insecticide and molluscicide that inhibits acetylcholinesterase (AChE).1,2 It induces mortality of tobacco budworm larvae when applied at a concentration of 0.56 kg/hectare and southern armyworm larvae at a concentration of 0.01 and 100 ppm.3 Methomyl is toxic to the land snail M. obstructa (LD50 = 11.9 µg/snail).2 It is also toxic to rats via oral but not dermal administration (LD50s = 30 and >2,000 mg/kg).1 Formulations containing methomyl have been used in the control of insects in agriculture.
1.Authority, E.F.S.Conclusion regarding the peer review of the pesticide risk assessment of the active substance methomylEFSA Scientific Report2221-99(2008) 2.Hussein, H.I., Al-Rajhy, D., El-Shahawi, F.I., et al.Molluscicidal activity of Pergularia tomentosa (L.), methomyl and methiocarb, against land snailsInt. J. Pest Mgt.45(3)211-213(2010) 3.Wolfenbarger, D.A., and Redfern, R.E.Toxicity of five carbamate insecticides to the two-spotted spider mite and larvae of the southern armyworm and the tobacco budwormJ. Econ. Entomol.61(2)580-581(1968)