GLENS FALLS, N.Y. -- Most people who spend a lot of time outside, especially in this hot, humid weather, like to spray on bug repellent to keep the mosquitoes away. And most of those sprays contain DEET.

Warren County Public Health Educator Dan Durkee said, "It's a combination that the Army came up with to protect their soldiers and then it came out in the 1950s."

It's a chemical that's proven highly effective in repelling bugs, but experts say pregnant women and children have to be careful when using it.

Durkee said, "With young kids, avoid putting it on their skin. If you can, put it on their clothing before they put it on, children under two especially, and don't put it on their hands because we know kids like to put them in their mouths. Don't apply directly to wounds or face."

That's because DEET has been linked to some severe side effects in kids. One is memory loss, but it has only affected a handful of kids.

"There have been some cases that they're not sure if it's specifically the cause, but it could have been linked and that's why you have to be careful with the way you use it on kids," said Durkee.

Nowadays there are some greener methods people are using to keep the bugs away. Products containing citronella and lemongrass are on the rise. But experts say right now, nothing beats products with Deet.

Durkee said, "There are other products out there, but either their effectiveness is up in the air or hasn't been tested enough. Deet has been shown to be the most effective."

Durkee said even natural products can cause side effects and the best bet is to take the manufacturer's warnings seriously. He also said while there are some documented cases of severe side effects with DEET, 50 to 100 million people a year use it and most are fine afterward.