MONTREAL - University researchers allege Imperial Tobacco Canada destroyed research that included scores of studies showing the devastating impact of smoking.

The University of Waterloo researchers have examined 60 scientific studies conducted between 1967 and 1984, and published their findings in the Canadian Medical Association Journal.

They say that one of the studies shows tobacco company researchers exposing hamsters to cigarette smoke, and concluding that they developed cancerous lesions as a result.

They also say the studies demonstrate that second-hand smoke is even worse than first-hand smoke.

The researchers say the documents were destroyed in Canada in 1992 at the request of British American Tobacco but copies are stored at British American Tobacco headquarters in the United Kingdom.

Researchers say the studies were conducted under a project codenamed Janus -- the two-faced god of Roman mythology.

Imperial Tobacco was not immediately available for comment, but spokesmen have said in the past that no original documents were ever destroyed.

The province of Ontario recently filed a $50 billion lawsuit against a dozen Canadian firms and their parent companies, including Imperial Tobacco Co., over smoking-related health costs. Other suits have been filed by the British Columbia and New Brunswick governments.