Picaridin vs. DEET
Which is the best insect repellent?
By Matt Heid
AMC Outdoors, July/August 2012
For more than 50 years, DEET has reigned as the undisputed champion of insect repellents. No longer. There's now a potentially better alternative on the market: picaridin. Both DEET and picaridin are proven to be effective at fending off mosquitoes—and are superior to other repellents when it comes to protection time. But which one is really the best? Who will win this face-off of the buzzer beaters?
DEET: Hard to beat
But DEET has some notable drawbacks. It imparts a greasy feel to the skin upon application. It emits a distinctive—and to many, unpleasant—odor. And it has the ability to dissolve certain plastics and some synthetic materials, including rayon, spandex, and vinyl. This is a particular hazard for sunglasses and plastic eyeglass lenses. (It has no effect on nylon, wool, or cotton.)
Picaridin: The new champion?
Studies have shown picaridin to be as effective as DEET in repelling mosquitoes. Unlike DEET, however, picaridin is odorless, non-greasy, and does not dissolve plastics or other synthetics. The one possible concern with picaridin is its relative newness. Insufficient time has passed for long-term health risks (should they exist) to manifest themselves. A limited, but growing, number of repellents contain picaridin, including Cutter Advanced, Sawyer Premium, and Repel Smart Spray.
How concentration affects protection time
A landmark 2002 study in the New England Journal of Medicine compared the efficacy of DEET at different concentrations and found that the duration of complete mosquito protection ranged from one to two hours for concentrations between 5 and 10 percent, four to five hours at around 20 percent, and only marginally longer up to 50 percent, with no improvement at higher levels. "Slow-release" formulas can extend protection time to eight hours or more. When it comes to picaridin, recent studies have indicated that a concentration of 7 percent is equivalent to about 10 percent DEET (one to two hours of protection), and a 20 percent concentration offers the same protection (four to five hours) as an equivalent DEET concentration.
Protection against other biting insects