Thorium 230 determination in polluted lake water — A study of interferences

The effect of contaminants, both known and unidentified, in interfering with the coprecipitation of ²³⁴Th tracer with BaSO₄ is described. The effect is illustrated by results obtained on water from Nero Lake, a uranium mine tailings dumping area. While most of the components of the water are known, attempts to duplicate the effect using synthetic water were less successful. Thus some strongly interfering substance in the water remains to be identified. A successful alternative method for Ra and Th determination is mentioned.