Yet smoking bans have remained a hard sell, as lawmakers and business owners debate whether such prohibitions are worth the anger from smoking customers and employees.
“The evidence is clear,’’ said Dr. Thomas Frieden, head of the US Centers for Disease Control and Prevention, which requested the study. “Smoke-free laws don’t hurt business . . . but they prevent heart attacks in nonsmokers.’’
Among the report’s conclusions: While heavier exposure to secondhand smoke is worse, there is no safe level. It also cited compelling if circumstantial evidence that even less than an hour’s exposure might be enough to push someone already at risk of a heart attack over the edge.
That’s because within minutes, the smoke’s pollutionlike small particles and other substances can start constricting blood vessels and increasing blood’s propensity to clot, both key heart attack factors. Yet many people do not know they have heart disease until their first heart attack, making it important for everyone to avoid secondhand smoke, Benowitz said.
Many of the institute’s committee members were skeptical they would find much benefit from the bans, said statistician Stephen Feinberg of Carnegie Mellon University. He called himself “the resident skeptic’’ who changed his mind.
“There was a clear and consistent effect of smoking bans,’’ Feinberg said.
Twenty-one states and the District of Columbia have what the CDC calls comprehensive laws banning smoking. That means 41 percent of Americans are as protected in public from secondhand smoke as possible, Frieden said. Just 5 percent of the world’s population is covered by comprehensive laws.
