12 MAY 1984, Page 19

Cancer

Sir: Brian Inglis's review of The Apocalyptics: Politics, Science and the Big Cancer Lie (Books, 28 April), reminds me of some information that has disappeared from view. Many years ago, the Times regularly published a short article summarising original work in science. One of these recorded that two physicists, being dissatisfied with statistical correspondence as evidence that cigarette smoking causes cancer, searched for the reason why it should. They found that the air in industrialised lands is laden with very fine radioactive dust. Tobacco leaves, covered with downy hair, collect concentrations of such dust, so smokers who inhale are depositing radioactive material on their lungs. This suggests to me that it is not specific substances, but radioactivity, that stimulates cancer growth. Mankind has always suffered from cancer, because there is an irreducible minimum of radiation from the earth's crust, and from the stars, including the sun. It seems that without the radioactive factor cigarette-smoking would cause bronchitis but not cancer. Possibly radioactivity is the determining factor in the many other substances believed to cause malignant tumours.

I apologise for being unable to provide more precise information about the Times article. When I had a paralytic stroke I lost my collection of press cuttings.

Mary A. Lynch

St Joseph's Nursing Home, 15 Church Street, London N9