Is there any truth to reports that concrete buildings are radioactive?
Yes, but it doesn't seem to justify any anxiety. All structures are somewhat radioactive, but masonry materials, including concrete and brick, show greater radioactivity than wood. The Royal Swedish Academy of Science recently completed one of the broadest studies of this problem ever undertaken. It found the greatest radioactivity in buildings of light concrete containing alum slate. The phenomenon has nothing to do, of course, with the atomic age. We've been using radioactive materials for shelter ever since the first man holed up in a cave. In modern structures minute amounts of radium and thorium in the building materials appear to be the main source of radioactivity. Science hasn't yet determined if this natural radioactivity is good or bad for people. But studies conducted in a thousand Swedish homes failed to turn up any differences in the health of the inhabitants that could be attributed to differences in radioactivity, even though some houses were found to be as much as a hundred times more radioactive than others.