What Works Best for Mosquito Repellent?

Several chemicals are effective at repelling mosquitoes.

The female mosquito requires blood protein to assist in the development of her eggs. Saliva from the female is released into the region of the bite, potentially causing an allergic reaction in some people. West Nile virus is carried by certain species of mosquitoes. Mosquito repellents are needed as a precaution against harmful mosquito bites.

Repellents and the EPA

The Centers for Disease Control and Prevention recommend using a mosquito repellent with active ingredients that have been registered with the U.S. Environmental Protection Agency (EPA). The EPA conducts tests on products for potential adverse reactions in humans and efficacy before registering them. The active ingredient for mosquito repellents that tested highest in efficacy is DEET, chemical names: N,N-diethyl-m-toluamide or N,N-diethly-3-methyl-benzamide.

DEET

DEET was developed in the 1940s for the U.S. Army and became available to the private sector in 1957. It still remains the best protection against mosquito bites. DEET also repels midges, chiggers, biting flies, ticks and fleas. An effective percentage of the active ingredient DEET in a product for adults is anywhere from 10 to 30 percent. Children, however, should not use more than 10 percent DEET. OFF! Deep Woods contains to highest percentage of DEET at 23.8 percent with an average protection time up to 5 hours. Another product with a high percentage of DEET is Sawyer Controlled Release at 20 percent DEET and an average protection time of up to four hours.

Picaridin

The active ingredient Picaridin also tested high in efficacy by the EPA. Available in Australia, Asia, Europe and Latin America for many years, Picaridin hit the U.S. markets in 2005. Picaridin maintains effectiveness for four to eight hours and is non-greasy, odorless and doesn't irritate skin. Goready Insect Repellent has the highest content of Picaridin at 20 percent with the next highest being Cutter Advanced Sport at 15 percent.

Oil of Lemon Eucalyptus

The active ingredient oil of lemon eucalyptus or P-menthane 3,8-diol (PMD) is a plant-based repellent that provides "reasonably" long-lasting protection and is registered with the EPA. When pitted against mosquitoes, it ranked equal to low concentrations of DEET. A 40 percent formulation of oil of lemon eucalyptus gives you up to six hours of protection. Repel Plant Based Lemon Eucalyptus Insect Repellent contains 40 percent of the active ingredient and Cutter Lemon Eucalyptus Insect Repellent contains 30 percent.

References

• CDC: What You Need to Know about Mosquito Repellent
• University of Florida IFAS Extension: Mosquito Repellents; C. Roxanne Rutledge et al
• University of Nebraska Lincoln: Insects, Spiders, Mice and More; Barb Ogg
• University of Illinois Extension: Preventing West Nile Virus