Some 1% of all deaths worldwide are caused by second-hand smoke, according to the World Health Organization. Researchers say passive smoking results in close to 600,000 deaths a year from heart disease, respiratory diseases, asthma, and lung cancer. It takes an especially heavy toll on children, with 165,000 a year dying from smoke-related respiratory infections, largely in Africa and South Asia.
Experts say more needs to be done to educate people about the dangers of smoking in homes with children— they found 40% of children (and more than 30% of non-smoking adults) regularly breathe in secondhand smoke. "It's almost as if people are in denial," the chief of the British Lung Foundation tells AP. "They absolutely would not do something dangerous like leaving their child in the middle of the road, but somehow, smoking in front of them is fine."