Consumer Reports is sharing some happy news just in time for black fly season: For the first time since testing began, safer insect repellants are also the most effective. In a series of tests, the magazine found new products containing chemically synthesized compounds similar to or derived from natural ingredients performed better than repellants containing DEET that, in the past, have always topped all other competitors. Researchers tested 15 pump sprays and aerosol repellants on the forearms of participants (dubbed the "swat team"), then watched as they either stuck their arms in a box with 200 hungry, disease-free mosquitoes or had deer ticks unleashed on them. The highest-scoring products were made of 20% picaridin—which resembles a compound in black pepper plants—or 30% oil of lemon eucalyptus, and repelled bugs for a minimum of six hours.
Though both ingredients can cause minor injury or irritation, "those problems are much less severe than (with) DEET," which can cause rashes or even seizures, an expert says. Sawyer Fisherman's Formula made with picaridin scored highest, protecting against mosquitoes and ticks for eight hours, while Repel Lemon Eucalyptus stopped ticks for eight hours and mosquitoes for seven hours, Time reports. Researchers note concentration is key as a repellant containing 5% picaridin performed rather poorly. The tests showed DEET products are also effective, though a 15% DEET spray performed better than a 25% product, perhaps due to other ingredients. If you do choose a DEET spray, researchers say it should contain no more than 30% DEET. What doesn't work: citronella, lemongrass, rosemary, and some plant-oil sprays, which couldn't keep bugs at bay for 30 minutes.