The EPA categorizes it as toxicity class IV - practically nontoxic. It is used against a wide range of fungal diseases of field crops, fruits, nuts, ornamentals, mushrooms, and turf. Formulations include wettable powder, dry flowable powder, and dispersible granules. Formulations include wettable powder, dry flowable powder, and dispersible granules. Skin reactions have also been seen in rats and guinea pigs.
Most organisms can become sensitized to the compound as well.
Benomyl is readily absorbed into the body by inhaling the dust, but there are no reports of toxic effects to humans by this route of exposure. Male rats had decreased sperm counts, decreased testicular weight, and lower fertility rates. Conflicting negative and positive results have been found in numerous mutagenicity assays. After 18 hours, only 5-HBC was present. No residues were found in muscle or fat.