Journal or Publishing Institution: Journal of Pesticide Reform
Study: http://eap.mcgill.ca/MagRack/JPR/JPR_22.htm
Author(s): Swadener, C.
Article Type: Journal Publication
Record ID: 2242
Abstract: Bacillus thuringiensis (B.t.) is a live microorganism that kills certain insects and is used to kill
unwanted insects in forests, agriculture, and urban areas. In a purified form, some of the proteins produced by B.t. are acutely toxic to mammals. However, in their natural form, acute toxicity of commonly-used B.t. varieties is limited to caterpillars, mosquito larvae, and beetle larvae. B.t. is closely related to B. cereus, a bacteria that causes food poisoning and to B. anthracis, the agent of the disease anthrax. Few studies have been conducted on the chronic health effects, carcinogenicity, or mutagenicity of B.t. People exposed to B.t. have complained of respiratory, eye, and skin irritation, and one corneal ulcer has occurred after direct contact with a B.t. formulation. People also suffer from allergies to the “inert” (secret) ingredients. People with compromised immune systems may be particularly susceptible to B.t. Viable B.t. spores are known to exist for up to one year following application. Insect resistance to B.t. has been well documented. Genetic engineering may greatly expand use of B.t., speeding up the development of more resistance. Large-scale applications of B.t. can have far-reaching ecological impacts. B.t. can reduce dramatically the number and variety of moth and butterfly species, which in turn impacts birds and mammals that feed on caterpillars. In addition, a number of beneficial insects are adversely impacted by B.t. B.t. is less toxic to mammals and shows fewer environmental effects than many synthetic insecticides. However, this is no reason to use it indiscriminately. Its environmental and health effects as well as those of all other alternatives must be thoroughly considered before use. B.t. should be used only when necessary, and in the smallest quantities possible. It should always be used as part of a sustainable management program.
Keywords: Bacillus thuringiensis, Bt, Toxicity, B. cereus, B. anthracis, Anthrax, Environment, Environmental Effects, Health, Health Effects, Sustainability
Citation: Swadener, C., 1994. Bacillus thuringiensis (BT): Insecticide fact sheet. Journal of Pesticide Reform, 14(3), pp.13-20.
