Temporary image - a photo of the diagram used in the printed Handbook.
Correlation does not prove causation - there is a strong correlation between
ice-cream sales per month and amputation of toes by lawnmowers!
Handbook of Radon.
30. Radon and Leukaemia.
One of the most emotive issues concerning radon is a possible link with childhood and other leukaemia. At the present time, there is scant if any evidence for a link between any type of leukaemia and radon exposure. Nevertheless intriguing work published recently has shown that cells may be damaged by alpha particles but that this may be expressed only after cell divisions.
It is important to appreciate both that leukaemia is a very rare disease, and that the causes of many types of leukaemia are not known. In these circumstances, but knowing that some types of leukaemia 'cluster' geographically, some scientists have placed substantial confidence in simple correlation studies. These have been used to suggest a link between average radon exposure and average incidence of leukaemia, both for regions of the UK and for different countries.
However, not only are the correlations weak and some of the data suspect (especially that on radon measurements) but it is a simple but often forgotten scientific fact that "Correlation does not prove Causation." An example to illustrate this is shown below: a correlation clearly exists between the number of people who cut off their toes with lawn-mowers each month, and ice-cream sales. However, few scientists would claim that closing down the ice-cream industry would help prevent garden accidents. Yet based on little more than weak simple correlations, claims have been made that radon causes leukaemia. A firm causal link has not been established.
Whether or not radon is weakly linked with some types of leukaemia, it should be noted that many more patients are now cured than was possible even a decade ago. Further information on all aspects of this group of cancers can be obtained from the Leukaemia Research Fund.
Temporary image - a photo of
the diagram used in the printed Handbook.
Correlation does not prove causation - there is a strong correlation between
ice-cream sales per month and amputation of toes by lawnmowers!
KEY FACTS:
There have been some questionable studies published recently in relation to radon and leukaemia. These have produced a predictable amount of Press speculation, and much anxiety. It may be recommended that future studies be based more around facts rather than principally upon the seductive mythology of weak correlation. Studies showing latent cell damage from alpha particle irradiation have so far only highlighted the question of radon links to leukaemia. Whatever the outcome of further studies, it must be recognised that leukaemia is a rare disease. The scope for prevention may be very limited even if radon is eventually implicated.