Scientists funded by Cancer Research UK are among thousands of academics with pensions invested in the tobacco industry, it has emerged.
The pension fund for university staff owned £211 million in British American Tobacco as of March 2015, its fifth biggest equity holding.
Cancer Research UK ensures that its employees' pension funds are free of tobacco industry investments.
However, the charity funds many full-time academic posts at British universities whose pensions are invested through the Universities Superannuation scheme (USS), worth £49 billion in 2015.
Universities UK, which represents vice-chancellors and principals, said the USS was a responsible investor, but public health campaigners argue it is not possible to reform the tobacco industry and have called on investors to dump their holdings.
The tobacco investment has come as a shock to many researchers, academics and staff, many of whom have spent their working lives searching for cancer cures.
George Butterworth, Cancer Research UK's tobacco policy manager, said: "The tobacco industry's deadly products are responsible for one in four cancer deaths.
"Many people would be shocked to learn that their pensions are invested in tobacco company shares - especially those striving to develop cures for diseases caused by this lethal industry.
"To help make it easier for organisations' pension schemes to opt out of tobacco shares, we're now funding the UK arm of Tobacco Free Portfolios to encourage investment funds to divest form tobacco stocks."
However, Universities UK defended its pension strategy.
"USS, as part of its investment duties, takes into account wider social, ethical, and environmental and governance issues, so long as that ensures that the assets of the scheme are invested in the best financial interest of members and their beneficiaries," said a spokesman.
"USS is also a responsible and engaged investor.
"They have for example, undertaken engagement with tobacco companies on marketing approaches and regulations around e-cigarettes."