British American Tobacco has revealed it is testing a new "less toxic" tobacco.
The cigarette manufacturer, which owns brands such as Lucky Strike, Kent and Pall Mall, has made three prototype products for the £6m analysis.
The 22-week trial will be carried out in Germany on 250 volunteers by an independent research organisation.
The new cigarettes are made from tobacco that has been processed in different ways to generate fewer "toxicants" as it burns, and they have new filters that absorb harmful chemicals.
BAT's head of public health and scientific affairs David O'Reilly said that the tobacco industry had been investigating cigarette safety for decades.
"The study is part of a larger scientific programme looking into potentially less risky tobacco products. We are trying to develop technologies that reduce toxicants in cigarettes in laboratory tests," he said.
When low-tar and light cigarettes were launched in the 1970s and '80s they were promoted as being safer to smoke on the basis of tests done on machines that simulated smoking. However, the findings were later found to be incorrect as real smokers puffed harder to get a nicotine hit.
