Pity the poor mosquito magnet. At any picnic or barbecue, the bugs are all over him like a cheap suit, while everyone else dines pest-free. It's not your imagination; it's chemistry. Some people really are more appealing to mosquitoes. And scientists are just beginning to understand why.
"People differ in their ability to attract mosquitoes, and each person's attractiveness can even change from day to day," says Ulrich Bernier, a chemist at the U.S.D.A.'s Mosquito and Fly Research Unit in Gainesville, Florida. Bernier and his colleagues have analyzed hundreds of natural compounds from human skin and have already identified several chemicals that act as attractants and some substances that seem to cloak the human bouquet. These elixirs combine to make some individuals three times more tempting than others. "We suspect the overall response of mosquitoes to humans is based not only on attractants but also on compounds that help hide us," says Bernier.
