Organic Insect Repellents

Neem tree leaves have serrated edges.

Mosquitoes, black flies and other biting insects can turn outdoor activities, like picnics and cookouts, into incredibly uncomfortable situations. Fortunately, several manufacturers produce insect repellents. The majority of these repellents, however, contain the synthetic chemical DEET, which is N,N-diethyl-meta-toluamide. And while the Environmental Protection Agency, or EPA, considers DEET safe to use -- when used as directed -- some people dislike the chemically odor associated with DEET-based repellents. Organic insect repellents represent a more natural alternative.

Lemongrass Oil

Lemongrass is a tropical, perennial herbaceous plant that yields a fragrant, lemon-scented oil. People -- especially those in southeastern Asia, where lemongrass grows natively -- use this oil for cooking and for producing medicines and perfumes. Lemongrass oil is also useful as an organic insect repellent, as it contains the compound citral. Citral has a low toxicity, but it is not strong enough to affect the human immune system. In contrast, lemongrass oil interferes with the pheromones of insects, causing physiological distress.

Lemon Eucalyptus Oil

Lemon eucalyptus oil comes from the Australian lemon eucalyptus tree, Corymbia citriodora. According to the University of Nebraska-Lincoln, the oil contains the compound PMD, which actively deters insects, including mosquitoes. A formula containing 40 percent PMD is typically able to provide six hours of insect protection after application. The downside to using lemon eucalyptus oil as an organic insect repellent, however, is that it can cause eye irritation. This is a result of the oil being mildly toxic.

Neem Oil

Neem is a tropical tree that is native to the Old World: Africa, Asia and Europe. Known in India as the "village pharmacy," the neem tree produces an oil that practitioners of the traditional Ayuredic medicinal system commonly prescribe for a variety of conditions. The oil is also effective at repelling mosquitoes and other insects, which is due its chemical composition. Neem oil contains the toxic limonoid compound azadirachtin, as well as the compound gedunin, which can help in the prevention of malaria.

Catnip Oil

Also known as cat mint, catnip is a Eurasian flowering plant in the mint family of plants. In addition to driving cats crazy, the fragrant oil from catnip plants can repel insects. The active ingredient in catnip oil is the organic compound nepetalactone. While the vapors of nepetalactone are intoxicating to cats, they are toxic to insects.

Warning

An organic or natural insect repellent does not necessarily entail a safe insect repellent. If you use highly concentrated natural oils as repellents without diluting them first, the toxic and irritating qualities of the oils have the potential to cause skin reactions and other health issues.

References

• TheDailyGreen: 7 Natural Insect Repellents; Brian Clark Howard
• Journey To Forever: Handmade Organic Mosquito Repellent; Keith Addison
• California State University, Los Angeles: Cymbopogon citratus; Victor Castillo; 2010
• University of Nebraska-Lincoln; What's the Scoop on Insect Repellants?; Barb Ogg; August 2008
• University of Florida IFAS Extension; Mosquito Repellents; C. Roxanne Rutledge and Jonathan F. Day; May 2005