Methomyl is an oxime carbamate insecticide that controls a broad spectrum of
arthropods such as spiders, ticks, moths, fl ies, beetles, aphids, leafhoppers, and spider
mites often found on various fi eld crops, ranging from fruits to tobacco (Kidd
and James 1991 ) . Methomyl is formulated as a soluble concentrate, a wettable powder
or a water-soluble powder (Kidd and James 1991 ) and is the active ingredient of
Du Pont 1179™, Flytek™, and Kipsin™, among other trade formulations (Kamrin
and Montgomery 1999 ) . Furthermore, the main formulated water-soluble products
contain approx. 25–90% methomyl, whereas the water-miscible products only contain
some 12.5–29% (IPCS 1995 ) . Methomyl is weak-to-moderately persistent,
with a soil half life ( t
1/2 ) ranging from a few to more than 50 days; however, under
ideal fi eld conditions the t
1/2 should be no longer than 1 week (IPCS 1995 ) .