Unlike most insecticides, which target a broad spectrum of species, including both pests and beneficial insects, Bacillus thuringiensis (Bt) is toxic to a narrow range of insects. Research suggests that Bt does not harm the natural enemies of insects, nor does it impair honeybees and other pollinators critical to agroecological systems. Bacillus thuringiensis (Bt) integrates well with other natural controls and is used for integrated pest management by many organic farmers.
The use of insect-resistant Bacillus thuringiensis (Bt) plants can potentially reduce use of chemical insecticide sprays, which are extremely toxic and expensive. Applications of conventional pesticides recommended for control of the European corn borer, for example, dropped by about one-third after Bt corn was introduced.
Although lethal to certain insect species, Bacillus thuringiensis (Bt) toxin applied as an insecticide or consumed with GMO food crops is considered nontoxic to humans and other mammals because they lack the digestive enzymes needed to activate the Bacillus thuringiensis (Bt) protein crystals. However, any introduction of new genetic material is potentially a source for allergens, and, for this reason, certain strains of Bt are not approved for human consumption.