The Brazilian Institute of Environment and Renewable Natural Resources (Ibama) has announced new measures to limit the use of pesticides containing thiamethoxam, a substance that affects the nervous system of bees and other pollinators. The decision, published on February 23, 2024, bans the aerial and terrestrial spraying of the insecticide, and reinforces the restrictions of use in several crops due to the lack of scientific data that eliminate the hypothesis of environmental risk.
Thiamethoxam is a neonicotinoid, a class of insecticides that has been widely used in Brazil in crops such as soybean, cotton, rice, and beans. However, studies have shown that the substance can disorient the bees, impair their learning, digestion, reproduction, and immune systems, and even cause their death. Due to its impact on the pollinators, thiamethoxam has been restricted or prohibited in several countries.
The new measures taken by Ibama are the result of an environmental re-evaluation process that started in 2018, following the guidelines of the Manual for Environmental Risk Assessment of pesticides for bees. The process involved the analysis of scientific studies, the consideration of other countries’ positions, and the consultation with representatives of the private sector, academia, and society.
According to the decision, the use of thiamethoxam as an active ingredient will no longer be authorized in 10 crops, such as potato, eggplant, onion, and eucalyptus. In other 25 crops, such as barley, corn, soybean, and wheat, the substance will continue to be allowed with restrictions, such as the application on the seeds or by direct spraying on the soil. The labels and leaflets of the products containing thiamethoxam will have to include a warning of toxicity for bees, as well as the new restrictions of application.
The Ibama’s decision aims to protect the bees and ensure that they continue to provide ecosystem services, such as the pollination of crops and native plants. Pollinators are essential for the maintenance of biodiversity and food security, and their decline can have serious consequences for the environment and human well-being.
In January, Ibama also restricted the use of fipronil, another substance toxic to bees. The aerial and terrestrial spraying of the insecticide on the entire area, that is, not directed to the soil or the plants, was banned in the national territory.