though most of these deaths will be among people who smoke. Of the 19,000 deaths, only 160 are estimated to result from inhaling radon that was emitted from water used in the home though most of these deaths would also among smokers. As a benchmark for comparison, about 700 lung-cancer deaths each year can be attributed to exposure to natural levels of radon while people are outdoors.
The committee determined that the risk of stomach cancer caused by drinking water that contains dissolved radon is extremely small and would probably result in about 20 deaths annually compared with the 13,000 deaths from stomach cancer that arises from other causes.
Except in situations where concentrations of radon in water are very high, reducing the radon in water will generally not make a large difference in the total radon-related health risks to occupants of dwellings. Using techniques to reduce airborne radon and its related lung-cancer risk makes good sense from a public-health perspective. However, there are concerns about the equity of the multimedia approach.
The committee concludes that evaluating whether a multimedia approach to radon reduction will achieve an acceptable risk reduction in a cost-effective and equitable manner will be a complex process. It will require significant cooperation among EPA, state agencies, water utilities and local governments, especially because many of the communities affected by the radon regulation will be very small and they will need assistance in making decisions concerning the advantages or disadvantages of a multimedia program. Thus, each public water supply will find it necessary to study its own circumstances carefully before deciding to undertake a multimedia mitigation program instead of treating the water to reduce the radon dissolved in it.