Imagine my delight when I discovered a toothpaste that promised luminous teeth. I imagined lighting my way at night with a glowing smile, or even having British teeth brighter than those in the United States. Of course, I’m not so gullible to take this literally and can spot marketing hyperbole when I see it. Nevertheless, it was still disappointing because such a toothpaste did once exist. Called Doramad Radioaktive Zahncreme, it was genuinely luminous because it contained radioactive radium.
Marie and Pierre Curie first isolated radium in 1898 and by the 1910s its luminescent properties had developed into a craze. Science was naïve to the dangers of radium at that time and it was added to the most bizarre range of products. From cocktails, such as the radium highball, to glow in the dark radium ink and even Vita radium suppositories advertised, “for restoring sex power”.
James Chadwick was a physicist who had the misfortune of being in Germany at the outbreak of the first world war and interned in a prison camp. Chadwick convinced a guard to buy some Doramad Radioaktive Zahncreme for him and he used it to conduct simple experiments with a home-made electroscope constructed out of tin-foil. Whether he also attained a glow-in-the-dark smile history does not record. After the war Chadwick carried on working with radioactivity and went on to win the Nobel Prize for physics in 1935 for the discovery of the neutron.
I don’t think my purchase of luminous toothpaste will earn me a Nobel Prize but I checked it out with my Geiger counter and, predictably, I was disappointed.
Graham Lappin 