NIGHT shift workers may face an increased risk of cancer, say researchers.
The World Health Organisation is to classify shift work as a "probable" carcinogen, suggesting it poses a similar risk to agents such as anabolic steroids, ultraviolet radiation and diesel engine exhaust. The theory could have ramifications for millions of people, especially in the developed world, where one person in five works nights.
It would also mark an about-turn for the scientific community, which has previously discarded such notions.
Richard Stevens, a cancer epidemiologist and professor at the University of Connecticut Health Centre, admitted scientists had traditionally dismissed any link between night work and cancer as "wacky".
Two decades ago, he published a paper that suggested a link between exposure to light at night and the development of breast cancer. At the time he was trying to establish why breast cancer incidence suddenly shot up from the 1930s in industrialised societies, where night work was considered a mark of progress. Most scientists were bewildered by his proposal.
But in recent years, several studies have found that women working nights for many years are indeed more prone to breast cancer, and that animals which have their light-dark schedules switched grow more cancerous tumours and die quicker.
Source - Scotsman