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The Buzz on Mosquito Repellants

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For many, a more pressing nuisance than the Emerald Ash Borer is the common mosquito. For decades, bug sprays with a chemical called DEET have been the most effective way to ward them off. But there are some new repellants on the market – and even more to come. For the Environment Report, Julie Grant has the buzz on bug sprays.

Hot summer nights haven't changed all that much since 1957. Sure, they're selling sushi at ball parks these days. But, for the most part, people are still using the same bug spray. DEET was designed in the 1950s for military use. Stores started selling it soon after. At this kids' baseball game in northeast Ohio, there are as many opinions about DEET and bug sprays as there are people.

PERSON 1: I if I did use bug spray, I would use DEET. I heard that's the best.
PERSON 2: No, actually, I am concerned about any kind of chemical. I don't like to use it. I don't think it's necessary.
PERSON 3: I've been scratching all week.
GRANT: Why don't you use it?
PERSON 3: Stinks.
PERSON 4: Probably looking for something without DEET, of course, which is pretty much outlawed anyway.
CHILD: I have a bug bite on my neck.
PERSON 4: Yes, you do have a bug bite on your neck, which is why we need to go look for something.

Actually, DEET is not even close to being outlawed. It's used hundreds of millions of times each year – by backyard barbeque-ers and soldiers, alike. In all these years, there have been only fifty reports of skin problems or seizures – and those were attributed to gross overuse, and couldn't be definitely connected to DEET. But it is a plasticizer. If it touches your watch face, it will smear the plastic. And that makes people a little nervous. And while it does drive away a wide array of bugs, including mosquitoes that carry West Nile Virus, DEET does not protect against mosquitoes that carry malaria, or ticks that carry lyme disease and rocky mountain spotted fever.

The worst thing about DEET for lots of people is that stickiness and that evil smell. Trisha Branden is a health editor with Consumer Reports magazine. She says lots of people just don't like using DEET.

BRANDEN: But I think everyone has their own sensitivity, particularly when it comes to the smell and feel of DEET. It's better to have some protection than none at all.

Consumer Reports has surveyed bug sprays and crèmes on the market. They found that the higher the concentration of DEET, the longer it protects you from bugs. At the highest level, 98% DEET, it lasted half a day. But some products contain as little as 7% DEET because it smells so bad.

Some people want something else. The EPA recently approved a new chemical – called Picaridin. It smells better. Consumer Reports found that Picaridin products kept mosquitoes away for up to four hours. That's not too bad. It's better than the natural products. If you use soybean or peppermint oil, Branden says you'll probably have to reapply a lot – at least every two hours.

BRANDEN: If you compare that to Picaridin product or the low DEET products, that is not nearly the protection.

Chemist Ulrich Burnier is on a team researching the next generation of bug sprays. He believes there are more effective chemicals out there. They've tested thousands of chemicals and narrowed it down to seven.

BURNIER: If we're successful, the ideal product will give you 24 hours protection, so you only have to apply once a day, you'll be protected around the clock. It's not a plasticizer. And, actually, this morning, I spent time trying to pick up odors from these seven compounds, and none of us participating in this study could detect any disagreeable odors from any of these compounds.

DEET still works pretty well. But mosquitoes and other invading insects are thriving. As we experience climate change, levels of mosquito-borne diseases like malaria are on the rise.

When you're at your nephew's baseball game, and fending off bugs, you might need to be a little patient. It could take a few years. But experts say you should be able to find new products that you like and that work for you.

For The Environment Report, I'm Julie Grant.


Music Button: Pearl Jam, “Bugs”, from the CD Vitalogy, (Epic records)

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