Shedding light on sunscreen safety

By Stephen Smith, Globe Staff

When it comes to one kind of sunscreen lotion, there can be too much of a good thing, a top Massachusetts health official cautions.

Some sunscreens are combined with a widely used mosquito-repellant called DEET to protect against the sun's rays and bugs' bites all at once. But Suzanne Condon, director of the state's Bureau of Environmental Health, urged careful use of the combination product, especially if you're going to need to repeatedly slather on protection against the sun.

While reapplying sunscreen is a good idea, it's not necessary to repeatedly douse yourself with DEET. It's advice, she said, that's especially important for parents to hear.

"If you use the DEET-sunscreen combination, then you're really going to give a child a much higher dose of the DEET," Condon said. "You don't want to keep applying pesticide when the real goal is to prevent the child from being sunburned."

The US Centers for Disease Control and Prevention categorically recommends against using the combination product because of the same concerns. Instead, the CDC recommends wearing long sleeves and pants to ward off both sun exposure and insect bites. And bug repellant can be applied to clothing rather than directly on the skin.