Thorium (Th)Because most thorium salts are excreted via urine, a high urine thorium level indicates exposure and probably increased body burden of this element. Thorium is considered mildly toxic for two reasons, low-level radioactivity and slight biochemical toxicity. Thorium is a radioactive element having 7 isotopes with half lives that exceed one hour. Thorium 232 constitutes 99% of the naturally occurring thorium and this is the isotope measured. Thorium 232 has a half-life of 1.4x10 to the tenth years. It decays by alpha emission to produce radon, Radon 228. In turn Radon 228 (half life 6.7 years) decays to other radioactive isotopes, eventually reaching lead. This radioactive decay process produces alpha, beta and gamma emissions. Several decades ago, a thorium (Thorium O2) suspension ("Thorotrast") was used diagnostically as a radiopaque agent. After a long period of latency, an unusually high proportion of individuals who received this procedure have developed leukemia, granulomas, and malignant liver tumors. These are slowly-developed diseases often with 20-30 year periods before onset or definite diagnosis. The biochemical effects of thorium are mild. Reactive thorium salts at high levels may inhibit amylase and phosphatase enzymes. Most orally ingested thorium, if not excreted in urine, binds to bone tissue where it has a long biological half-life (years). There is a literature report for abnormal lymphocytes in animals following a thorium challenge. Thorium has about the same abundance in the earth as does lead and is encountered in mining activities for titanium and rare earth elements. Commercially, thorium is used in incandescent gas lantern mantles, refractory materials (thorium melts at 3300 degrees C), and as a coating for tungsten in electronic applications. It is present in nuclear fuels (Uranium 235 decays to Thorium 231). Thorium may also be present in tungsten-inert-gas ("TIG") welding electrodes.
If you suspect that you have an elevated Thorium level, it is important to determine total body load. Here at Chelation Medical Center we can do an IV chelation provoked challenge. Just give us a call.