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Letter on Active and Inert Ingredients in Minimum Risk Pesticides

In November 2005, EPA sent a letter to state pesticide agencies to explain why certain products were not eligible for the exemption from regulation under FIFRA Section 25(b). Specifically, the letter addresses the issue of an ingredient listed as an active ingredient not actually being the ingredient that would kill the target pest, even though it is on the active ingredient list in the exemption criteria. The actual “active” ingredient is listed as an inert and is not eligible to be used as an active ingredient in a minimum risk product.

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