(AP) -- By 2020, every state may have bans on smoking in restaurants, bars and the workplace, federal health officials predicted Thursday, based on the current pace of adopting anti-smoking laws.
The number of states with comprehensive indoor smoking bans went from zero in 2000 to 26 in 2010.
"It is by no means a foregone conclusion that we'll get there by 2020," said Dr. Tim McAfee, director of the CDC's Office on Smoking and Health.
But the success of the smoking ban movement has been astounding, and seems to be accelerating, he added. "I'm relatively bullish we'll at least get close to that number."
Nearly half of U.S. residents are covered by comprehensive state or local indoor smoking bans, the CDC estimated, in a new report.
Another 10 states have laws than ban smoking in workplaces, bans or restaurants, but not in all three venues.
Some other states have less restrictive laws, like requiring smoking areas with separate ventilation.
Only seven states have no indoor smoking restrictions, although some of their cities do: Indiana, Kentucky, Mississippi, South Carolina, Texas, West Virginia and Wyoming.
Gary Nolan, director of a smokers' rights group, said he wouldn't be surprised if the CDC's prediction came true. Public health officials and others have been putting tremendous pressure on bars and businesses to bar smoking, he added.
"It wouldn't surprise me if they prevailed," said Nolan, of the Smoker's Club. "It's just a little bit more liberty slipping away at the hands of big government."
Tobacco smoke is an established cause of lung cancer, heart disease and other maladies, and smoking has been called one of the nation's leading causes of death.
The science on the impact of smoking bans is younger. Because it takes years or even decades for cancers to develop, there's little information on the impact of bans on cancer rates. But studies have already charted declines in adult heart attack rates and in childhood asthma attacks after smoking bans were adopted in some communities.
The American Heart Association's chief executive, Nancy Brown, said the CDC report brings good news. But she said advocates have a lot of work ahead of them to make the 2020 prediction come true.
"It's too soon to rest on our laurels," she said, in a prepared statement.
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