August 17, 2009

Better mosquito repellents are developed

U.S. scientists say they've created new mosquito repellents that perform better than DEET, the most used chemical to repel the disease-carrying insects.

U.S. Department of Agriculture researchers said their new repellents work three times longer than DEET, eliminates DEET's unpleasant odor and don't cause DEET's sticky-skin sensation.

But scientists caution the new repellents might never find a place on store shelves.

Ulrich Bernier, the USDA's lead researcher for the repellent study, said the costly, time-consuming pre-market testing and approval process is a hurdle that will delay availability of the repellents, which were discovered last year. He said topical repellents can take years and a significant investment to reach the retail marketplace.

Provided the repellents work well when tested on human skin, and if they pass the battery of toxicological tests, they would still face a series of tests to prove their effectiveness in repelling mosquitoes, Bernier said.

Clearly, the odds are stacked against new repellent products making it to market, he said.

Bernier and post doctoral researcher Maia Tsikoli presented the research Sunday in Washington during the 238th national meeting of the American Chemical Society.