A leading figure in Shanghai's fight against smoking has insisted that a total ban will make a difference in people's health - despite research finding the problem has worsened in areas where restrictions are already in effect.

The city introduced a partial ban on March 1, 2010, and listed 16 types of public places that were required to implement smoking areas, mainly entertainment venues. It also states schools and maternity and children's hospitals must be smoke-free zones.

However, health inspections at Internet cafes, KTV bars and restaurants discovered the prevalence of smoking had actually risen - from 0.3 in 2011 to 0.4 in 2012.

Li Guangyao, one of the architects of Shanghai's anti-smoking strategy, conceded that the data show many problems still exist with management and enforcement.

"There is no consistency about how big or where a smoking area should be," Li said. Under the rules, only restaurants with 75 seats or more must establish a smoking zone.

"It's obviously unfair," said the deputy director of the Shanghai Health Promotion Committee. "A complete smoking ban will change that, though. It will mean people can't smoke anywhere, in large or small restaurants,"

Li said the rise in the prevalence of smoking in bars, restaurants and Internet cafes is mainly because business owners do not want to risk upsetting customers. About 90 percent of fines issued in 2012 were for those types of venues.

Yet he acknowledged that insufficient enforcement has also played a part.

Although in force since early 2010, Shanghai police only joined the anti-smoking campaign last year, which may explain the dramatic jump in fines issued - 192 venues, 101 smokers and a total of 348,000 yuan ($56,000) in 2012, compared with 78 venues, 10 smokers and 182,800 yuan over the previous two years.

The public security bureau also began last year to fine venues 50 to 10,000 yuan in accordance with a regulations on fire hazards.

"We'll be strengthening supervision and enforcement in the worst areas," Li said, adding that the Shanghai Health Promotion Committee, district health departments and academic bodies are now working on legislation for a complete ban.

"Over the past three years, awareness of the harmful effects of smoking has improved through education," he said. Li vowed the city will step up campaigns to get the message across.

Judging from a recent survey of 15,000 Shanghai residents, 30 percent of whom were smokers, there is a demand for a total ban in public places.

More than 90 percent supported restrictions in all workplaces and public indoor spaces.

About 85 percent also said densely populated areas, such as pedestrian shopping streets, should be included, and 89.3 percent said anti-smoking efforts should be part of the annual evaluations for units.

A series of surveys of hospitality workers, hotel guests and restaurant patrons in recent years has demonstrated overwhelming support for stricter smoking controls.

"Smoking should be completely prohibited," said Fu Hua, a professor of public health at Fudan University. "Special areas for smokers can't prevent people being exposed to secondhand smoke."

Research by Fu's school and the Shanghai Health Promotion Committee found levels of PM2.5 - tiny particulate that can enter the lungs - rise by five times when a cigarette is lit in an enclosed space.

According to the Ministry of Health, almost the entire population of China is exposed to cigarette smoke. Three hundred million people including more than half of all men voluntarily light up, while another 740 million are exposed to secondhand smoke.

Since 2008, large cities such as Beijing, Shanghai and Guangzhou in Guangdong province have enacted regulations prohibiting smoking in public places, but none has completely banned the habit.

Harbin, capital of Heilongjiang province, became the first to do so in 2012, winning plaudits from health experts.

"Harbin's legislation to make it a smoke-free zone sets a good example for other cities," Yang Gonghuan, a tobacco control expert with the Chinese Center for Disease Control and Prevention, told Xinhua News Agency.

"An absolute ban in restaurants is a landmark for the country's anti-smoking mission," he added.

However, Li Guangyao warned that China still has a long way to go to meet the requirements set out in the World Health Organization Framework Convention on Tobacco Control, a treaty the country signed in 2003.

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