Old tobacco smoke a killer - report

Old tobacco smoke does more than simply make a room smell stale - it can leave cancer-causing toxins behind, Reuters reported today.

Researchers in the US found cancer-causing agents called tobacco-specific nitrosamines stick to a variety of surfaces, where they can get into dust or be picked up on the fingers.

Children and infants are the most likely to pick them up, the team at Lawrence Berkeley National Laboratory in California reported.

"These findings raise concerns about exposures to the tobacco smoke residue that has been recently dubbed `third-hand smoke'," the researchers wrote in the Proceedings of the National Academy of Sciences.