Lung cancer deaths attributable to indoor radon exposure in West Germany.

BACKGROUND

There is substantial epidemiological and experimental evidence that exposure to radon at levels found in underground mines can cause lung cancer. Although radon levels measured in homes are normally substantially lower, there is concern about the presence of a known lung carcinogen in a residential setting.

METHODS

Using national survey data on radon concentrations in homes in the former West Germany, the proportion and absolute numbers of lung cancer deaths attributable to radon are estimated. As lung cancer risk models derived directly from residential radon studies are not yet available, the risk model developed recently by Lubin et al. from a joint analysis of 11 underground miners' studies is applied. For an estimate of the impact of smoking on radon-attributable lung cancers, three different approaches are used and compared.

RESULTS

Our analysis shows that after adjusting for dosimetry differences between mines and homes about 7% of all lung cancer deaths in the western part of Germany may be due to residential radon. This corresponds to a total of about 2000 deaths (95% CI: 500-8200), 400 in females and 1600 in males. Adjusting for the intermediate relationship for smoking and radon, the attributable risk is estimated to be about 4-7% for smokers and 14-22% in non-smokers.

CONCLUSIONS

Our analysis basically confirms the results of former calculations with regard to the total number of lung cancer deaths attributable to radon in West Germany. However, we show that the standard practice that applies the same model to smokers and non-smokers may result in biased estimates for these groups.