With West Nile Virus and Eastern Equine Encephalitis (Triple E) becoming more prevalent in the United States, consumers want and need to become more familiar with reading mosquito repellent labels. What is the active ingredient that makes one repellent more effective than another and when should a specific repellent be used? There are dozens of insect repellent formulations and hundreds of products today. When in doubt, it is best to look to the experts for advice.
The Center for Disease Control (CDC) recommends the use of products containing active ingredients that have been registered with the U.S. Environmental Protection Agency (EPA). These products have brand names that consumers recognize such as OFF, Cutter, and ThermaCELL — an area repellent that is up to 93 percent effective and is quickly gaining popularity. Area repellents are a good solution for parents who do not want to put harmful repellents on their child’s skin. When the EPA registers a repellent, it evaluates the product for efficacy as well as potential effects on human beings and the environment. EPA registration means that the 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. Repellents registered with the EPA have demonstrated a high degree of efficacy and contain active ingredients such as:
- Allethrin: a synthetic analog of a natural insecticide found in chrysanthemum flowers that is odor-free and is an alternative to lotions and sprays which must be applied to skin. Allethrin is an area repellent that is dispersed into the air and is up to 93 percent effective in fighting mosquitoes, black flies, and no-see-ums.
- DEET: (N-diethyl-m-toluamide). Repellents containing DEET are safe for adults and children when used according to directions. Don’t put repellents with DEET on kids’ hands because it may get in their mouth or eyes. The CDC warns: Use these repellents carefully as DEET in high concentrations may be harmful to kids.
- Permethrin: a cousin to Allethrin, is recommended for use on clothing, shoes, bed nets, and camping gear. Permethrin-treated clothing repels and kills ticks, mosquitoes, and other arthropods and retains this effect after repeated laundering. Permethrin is not to be used directly on the skin.
- Picaridin: (KBR 3023) forms a barrier on your skin, which blocks an insect’s ability to locate humans. Picaridin was tested against mosquitoes, flies and ticks in both field studies and in laboratory cage tests. Picaridin provides equal or longer protection than identical concentrations of DEET. Efficacy against ticks has been demonstrated in laboratory cage tests.
- Oil of Lemon Eucalyptus [p-menthane 3,8-diol (PMD)]: is a plant-based repellent. In two recent scientific publications, when oil of lemon eucalyptus was tested against mosquitoes found in the US, it provided protection similar to repellents with low concentrations of DEET.
What repellent should be used when?
| Hiking, biking or walking in cooler weather | Applying permethrin to your clothing ahead of time will provide protection. |
| Enjoying the patio, at a campsite or spectator sport; gardening at dusk or dawn | Area repellents, such as ThermaCELL products that use allethrin, provide hours of protection, are highly portable and create a 15 x 15 ft zone of protection. The hand-held units and lanterns are up to 93% effective in fighting biting insects and are affordable. The ThermaCELL lantern was voted #1 Tabletop Mosquito Repellent by the Good Housekeeping Institute. |
| Playing a sport at dusk or dawn | For many hours outside (over 3-4 hours) and/or where biting is very intense—look for a repellent containing more than 20% DEET. |
| Helpful Tips | – Even if you’re going outside for only 10 minutes use a repellent —that’s long enough to get bitten.
– Products with more than 50% DEET DO NOT offer additional protection. – For shorter periods of time, repellents containing less than 20% DEET, a repellent with 7% picaridin, or a product containing oil of lemon eucalyptus may provide adequate protection. |