Results of the Japanese study are reported in the Journal of the American Medical Association.
Researchers put 15 nonsmoking men in the same room with 15 smokers for 30 minutes. After the allotted time, the subjects were screened. The smokers, whose heart arteries already showed damage, had no additional ill effects. But the result in nonsmokers was a reduced ability of the heart arteries to dilate. That's a condition that other studies have showed could lead to hardening of the arteries.
American Heart Association President, Doctor David Faxon, says the study confirms the danger of secondhand smoke. He says if the exposure continues, the result can be gradual and irreversible artery damage.