A coauthor of a research paper that found cigarettes produced in China contained three times more heavy metals than in Canada-manufactured brands denied that the team conducted the research in order to help foreign cigarette brands enter the Chinese market.

The International Tobacco Control (ITC) Project published the paper in the UK-based journal Tobacco Control last month, raising concerns about tobacco industry practices and control policies in China, and the health impact had on people.

Li Qiang, a member of ITC, said in an interview with the Beijing Times that the research was part of a global project to assess the impact of the World Health Organization Framework Convention on Tobacco Control, a treaty China signed in 2006, on smoking-ban policies in member countries.

The research was sponsored by the US National Institute of Health and Canadian Institute of Health Research.

When asked whether the sponsoring agencies were impartial, Li replied that the research was not influenced by any tobacco company.

"This research is a health-related issue. You may think that we are helping foreign cigarette brands enter the Chinese market. That is only a smokescreen created by certain interest groups to shift the public's attention from health issues to trade issues," he said.

The team conducted similar research in 20 countries including the US, the UK, Canada and Australia, as well as some developing countries.

The research in China took four years and began at the end of 2005. Researchers from Canada, the US and the UK selected 78 Chinese cigarette brands purchased from seven Chinese cities between 2005 and 2007 for testing, 13 of which were found to contain excessive heavy metals, including Baisha from Hunan Province and Daqianmen from Shanghai.

"In order to maintain impartiality, we purchased the cigarettes when staff from the tobacco control office of the Center for Disease Control and Prevention and local office for disease control and prevention were on the scene," he said.

"When the results first came out, we were very surprised since the heavy metal content was much higher than those from other countries," he said.

However, he also pointed out that their paper appeared to have little impact on Chinese tobacco companies, which have not held direct talks with them since the research was published.

Consumption of cigarettes in China reached 38.9 million cartons last year, according to the China National Tobacco Corporation.