Five percent of Internet-browsing teenagers who took part in a recent survey watched at least one online video promoting alcohol or other drug use in the past month, Reuters reported Oct. 7

The study of 6,000 teenagers was conducted in June by Nielsen Online for the federal Office of National Drug Control Policy (ONDCP). ONDCP director John Walters said that 40 percent of the pro-drug videos watched by the teens, often hosted on social networking sites like MySpace, had explicit footage showing drug use or depicted youths who were drunk or high.

"Parents would be horrified to think that people are sneaking into their house to encourage their kids to build a bong or to chug on beer at age 13," Walters said. "The fact is those people are sneaking into your house through your Internet connection on your computer."

Walters urged parents to keep close tabs on their teens' online activities by checking web-browser and cellphone history logs to see what their child is viewing and doing.

An expert on youth Internet use said teens are using online tools to show off their alcohol and other drug use. "Kids already did stupid stuff, but what's new is kids are recording what they're doing and broadcasting it for the world in competition for a kind of celebrity," said Peter Zollo of TRU, a market research company. 

ONDCP has created an online primer, Digital Technology 101, to help parents understand and monitor their teens' online activities.