The U.S. has spent millions of dollars since the 1980s on anti-drug ads. But research shows that some of these older public service announcements might be counterproductive. Now that the ads are shifting to reach teens who want to rebel, new studies show they may actually be more effective.

It's hard to determine just how many veterans became ill because they were at nuclear test sites, but one soldier who witnessed more than 20 bomb explosions in the Nevada desert in 1957 says a lot of good men died because of it.