Passive smoking 'doubles hearing loss risk among teens'

Investigators say the findings, from a study of over 1,500 US teens aged 12 to 19, suggest that secondhand tobacco smoke directly damages young ears. And the greater the exposure the greater the damage.

It is still unclear how much exposure could be harmful and when the damage might occur. Experts already know that smoke increases the risk of middle ear infections. And they believe it may also harm the delicate blood supply to the ear causing "subtle yet serious" changes. "Further research is needed to demonstrate a causal link," said Dr Ralph Holme of the charity Action on Hearing Loss formerly RNID.