Ben's 100% DEET Mosquito, Tick and Insect Repellent, 1.25 Ounce Pump, 3 Count

Product Information

OLE, although it occurs naturally in the lemon eucalyptus plant, is not an essential oil. It’s refined and concentrated (or sometimes synthesized chemically) for use in commercial bug repellents. After 5 minutes, the subjects withdraw their arms, then repeat the process by placing their arms into a second pair of cages of disease-free mosquitoes of a different species for another 5 minutes. The subjects then walk around for about 10 minutes to stimulate sweating. That’s to mimic a real-world situation in which users might exercise while wearing repellent. Adults should dispense repellent on their hands to apply to children. Don’t spray repellent onto kids or apply it to their hands. That’s to avoid it getting into their eyes or mouth and avoid applying it to cuts or irritated skin. (Insect repellents with deet should not be used on children younger than 2 months.)

After 30 minutes, these volunteers then place their arms into the first two of four cages of 200 disease-free mosquitoes for 5 minutes. Our testers watch closely to see what happens inside the cage, and they count every time a mosquito lands on a subject’s arm, uses its proboscis (its long mouth) to probe the skin in an attempt to find a capillary, or bites the subject’s arm and begins to feed—which the testers can tell by watching for the insect’s abdomen to turn from gray to red or brown.Fourteen of our 22 recommended insect repellents use deet as their active ingredient. Three are made with 20 percent picaridin, one is made with 10 percent picaridin, and four contain 30 percent oil of lemon eucalyptus (OLE).

Our testing suggests that when it comes to effectiveness, what matters most is the type and concentration of active ingredient in the repellent. Just make sure you follow the label instructions and apply it in a well-ventilated area, Mather says. If you’re an avid hiker, consider snagging some pre-treated gear from a company like Insect Shield (as pre-treated clothes can last up to 70 washes, or about 10 times longer than the spray-on stuff).Still, if you want to avoid deet, 20 percent picaridin or 30 percent OLE are your best bets. More Importantly, in our testing, all of the so-called natural repellents—products whose active ingredients are essential oils—earn dismal scores. Frequent reapplication isn’t necessary. Wash your hands after applying and wash off repellent at the end of the day.