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Chemically-related Groups of Active Ingredients

Many pesticide active ingredients affect pests in similar ways, and we re-evaluate them together as a group. Examples of groups include: 
  • Carbamate insecticides are widely used in homes, gardens, and agriculture. They affect the functioning of the nervous system in ways similar to the organophosphates. The effects are usually reversible in humans.
  • Neonicotinoids: The neonicotinoids are insecticides that affect the central nervous system of insects. They have been associated with some bee kill incidents.  Neonicotinoid pesticide products are applied to leaves and are used to treat seeds.  They can accumulate in pollen and nectar of treated plants, which may be a source of exposure to pollinators.  We are in the process of reevaluating this class of insecticides under the registration review program so we can understand whether there are effects to honeybees and other pollinators that need to be addressed.
  • Organochlorine insecticides were commonly used in the past. Many, like DDT, have been removed from the market due to their health and environmental effects and their persistence (e.g., DDT and chlordane). Others, like dicofol, lindane, and endosulfan, are now only available in the U.S. for limited uses.
  • Organophosphate insecticides are used in agriculture, homes, gardens, and on animals. They affect the insect’s nervous system. Organophosphates range in toxicity for insects and humans (some are highly toxic), and they usually are not persistent in the environment. Our evaluation of risks from organophosphates resulted in the cancellation of several organophosphates and restrictions on the use of others. For example, parathion is no longer registered for any use, and chlorpyrifos is no longer registered for home use.
  • Pyrethrin and pyrethroid insecticides share a common origin. Pyrethroids are synthetic versions of the naturally occurring chemical pyrethrin, which is found in chrysanthemums. Pyrethrins are used mainly for indoor pest control. Synthetic pyrethroids are used in agriculture because they are designed to be more stable in the natural environment. Some synthetic pyrethroids are toxic to the nervous system. More information about pyrethrins and pyrethroids pesticides.

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