RADON UPDATE

The Morbidity and Mortality Weekly Report by the publishers of the New Engl. J. of Medicine has published a brief report on the risk from elevated levels of indoor radon. Approximately 5,000 to 30,000 deaths/year may be attributed to this cause in the US. Tables based on the NRCP report [AtE Sep 84] for the general population show the risk proportional to the radon concentration (in working levels, WL) and to the length of exposure to it. For people who spend 75% of their time in the home, the probability of dying of radon-associated lung cancer is 2.9% per WL per year of exposure. The EPA guideline for permissible indoor radon is 0.02 WL.

Radon levels are measured by detectors placed in the home for long periods (there is a pronounced seasonal variation, which is not uniform over the US). A proven type of detector is made by Terradex, Inc., of Walnut Creek, Calif. It records individual tracks left by particles incident on the detector material in the disintegration of radioactive atoms in the air. The material is etched to make the tracks visible and countable under a microscope.

A mail-order service using these detectors is advertised by Radon Measurement and Services, 1313 W. Cedar Dr., Lakewood, CO 80228 (303/980-5086). Prices depend on number of detectors (size of home) and range from $150 to $250. (My knowledge about the company is restricted to its advertisement.)