In 1987, Quebec made an important social by banning the use of chemical pesticides in forest environments. However, in relation to the epidemic management strategy adopted by the Quebec Ministry of Natural Resources, only one group of products has proven its efficacy : namely, insects disease bacteria such as decision of import to society by banning the use of chemical pesticides in forest environments.
What is Bacillus thuringiensis?
Btk is a bacterium that lives naturally in soils, where it was initially isolated. However, it can also be found in water or on vegetation even when no spraying has occurred. In keeping with the scientific literature on the subject, SOPFIM reached this conclusion on its own after performing annual environmental follow-up as part of its forest pest management programs. It is not uncommon to find low concentrations of Btk in watercourses, water intakes and in the soil prior to the start of operations.
How does the insecticide work?
Bacillus thuringiensis is a bacterium having the ability to produce a protein crystal that is converted into a toxin whenever it is placed in an alkaline environment. As it so happens, insects belonging to the order of Lepidoptera, which includes the main forest insect pests in Quebec, all have a basic (alkaline) digestive system. Whenever a lepidopteran feeds on foliage treated with Btk, the toxin released by the protein crystals destroys the walls of its gut, thus forcing the insect to stop feeding. Death usually occurs two to five days later. Btk must be ingested by the insect in order to produce a toxic effect.
Is Btk harmful to wildlife, flora or humans?
The organic pesticide known as Btk has been used in forest areas in Quebec since the mid-1980s, and has been used throughout the world in other sectors for more than 50 years now. In all these years, no serious infection and no public health problem have been reported. Btk is a safe product regularly used in different formulations in agriculture, gardening and public health; some formulations have even been approved for use in organic farming. As Btk has been approved for use in agriculture, both Health Canada and the US Environmental Protection Agency have prescribed no upper limit with respect to food.
What happens if animals eat an insect who ate the insecticide?
As is shown by the available scientific information, Btk can be ingested by human beings or any other mammal and pass through their acidic stomach without being activated i.e., without releasing any toxin.
As various studies have shown, Btk formulations are specific to insects belonging to the order of Lepidoptera and thus are not a source of impact to aquatic or terrestrial ecosystems.
