BEIJING (AP) -- Efforts to curb tobacco use in the world's most populous nation have had no real impact and 301 million Chinese are still smoking, China's Center for Disease Control said in a report.

A survey of more than 13,000 people earlier this year found no significant improvement in the country's smoking rate since 2002, China's CDC said in a joint statement released Tuesday with the World Health Organization and the United States CDC.

The survey also found that 72.4 percent of nonsmokers reported being exposed to secondhand smoke. Though China has pledged to make indoor public places, workplaces and public transport smoke-free by early next year, 63 percent of those surveyed said they had seen people smoking in public places or at work in the 30 days before they were interviewed.

"There has been no substantive improvement in the smoking rate or exposure to secondhand smoke," Yang Gonghuan, deputy director of China's CDC, was quoted as saying.

Yang said disease and death from problems related to smoking and secondhand smoke, such as cancer and coronary heart disease, were expected to "rise unabated" over the next 30 years.

"The burden on society will be immense and progress in public health will suffer as a result," Yang said.

The statement said the smoking rate for those aged 15 and older dropped slightly to 28.1 percent, or 301 million people, since 2002 but didn't give the earlier figure.

It said China's anti-tobacco policies needed to be strengthened and blamed low-priced cigarettes, ineffective health warnings on cigarette packaging and a lack of education about the health risks of tobacco for the high smoking rate.

The statement summarized the findings of China's portion of the Global Adult Tobacco Survey, a large sampling of 14 developing countries that hopes to provide a clearer picture of how tobacco is used and promoted.

The CDC said the survey was carried out by 500 staff who interviewed 13,354 people aged 15 and older between January and March in sample areas across the country. A margin of error was not provided.

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