Living close to heavy industry may increase the risk of developing lung cancer, although the effect is relatively modest, suggests research published ahead of print in Thorax.

Over 200 women under the age of 80 with primary lung cancer were compared with 339 healthy women matched for age and sex in Teeside, north east England.

Rates of lung cancer among women are high in this particular area of England, where heavy industry expanded rapidly throughout the nineteenth and twentieth centuries, and where poverty and deprivation are common.

By 1945, Billingham on Teeside was the larges single chemical production complex in the world, and houses for the workforce were built as close as possible to the industrial sites.

All the study participants were interviewed at length about their lives, including full histories of where they had lived, their employment, as well as their smoking habits, and exposure to second hand smoke.

The distances from heavy industry sites were grouped into three zones: less than 5 km (zone A) away; 5 to 10 km away (Zone B); and more than 10 km away (Zone C).

The average length of time that all participants had lived in the area was over 55 years.

After taking account of smoking and other factors likely to influence the results, the data showed that women who had lived in zone A for more than 25 years were almost twice as likely to develop lung cancer as those who had not lived there.

The findings are broadly consistent with those of other studies, say the authors, who suggest that the impact of air pollution on the development of lung cancer warrants further study.