Repellents are chemicals that interfere with the host-finding or feeding events of biting insects and ticks. Used according to label directions, they can protect people from bites by these arthropods. The Centers for Disease Control recommends using products that have been shown to work in scientific trials and that contain active ingredients which have been registered with the Environmental Protection Agency (EPA) for use as insect repellents on skin or clothing. When EPA registers a repellent, they evaluate the product for efficacy and potential effects on human beings and the environment. EPA registration means that EPA does not expect a product, when used according to the instructions on the label, to cause unreasonable adverse effects to human health or the environment.
EPA registered repellents:
- DEET (N,N-diethyl-m-toluamide) repels mosquitoes, biting flies, and ticks.
- Picaridin is registered as a skin and clothing application to repel mosquitoes, biting flies, ticks, and chiggers
- Oil of lemon eucalyptus (30%), derived from the leaves of the lemon eucalyptus tree, repelsmosquitoes.
- Metofluthrin is a vapor-active pyrethroid insecticide that repels mosquitoes. It is dispensed from a clip-on emantor.
There are insect repellent products for sale in the U.S. that do not have to be registered by EPA because the amounts of active ingredients in the products were determined to pose minimal risk to human health. Examples are citronella oil, cedar oil, geranium oil, peppermint and peppermint oil, and soybean oil.
Read and follow label directions carefully when using repellents.
By Lee Townsend, Extension Entomologist