Insect Repellents: Assessment of Health Risks

Abstract

Insects are known to be vectors for pathogens that cause diseases such as West Nile Virus, dengue, Lyme disease, and malaria. Insect repellents play an important role in personal protective measures against arthropod bites and the spread of the diseases they are known to carry. Insect repellents with current approval from the United States Environmental Protective Agency for application to the skin include N,N-diethyl-3-methylbenzamide (DEET), picaridin, MGK-326, MGK-264, IR3535, oil of citronella, and oil of lemon eucalyptus. Permethrin has both insect repellent and insecticide properties. Reported toxicity from these compounds, generally associated with inappropriate usage or excessive exposure, includes local effects such as contact dermatitis and irritant dermatitis, as well as the more rarely reported cases of neurotoxicity, cardiotoxicity, anaphylaxis, and death. Of note, the most commonly used insect repellent is DEET, which has maintained an excellent safety profile for more than 50years. Correct use of these products is paramount in avoiding toxicity. Products should only be used in accordance with manufacturer's guidelines with specific care to avoid over-application.