Fipronil is a biocide and acts as a highly toxic insecticide against fleas, mites, lice, and roaches. It is used as a contact poison mainly in pet care products to prevent and treat infestations of parasites.

Fipronil is not approved for use in food. Therefore, it may not be applied as a pesticide or veterinary drug in agriculture (exceptional permits exist, e.g. for combating wireworms in potatoes).

Products contaminated with Fipronil, regardless of the level of contamination, are considered unfit for sale and must be withdrawn from the market. According to a statement from the BfR (Federal Institute for Risk Assessment), a potential health risk cannot be ruled out at concentrations greater than 0.72 mg/kg of food.