Radium contamination of the banks of the river Laak as a consequence of the phosphate industry in Belgium

For over half a century, phosphate ores of marine origin, containing ²²⁶Ra, have been processed in Belgium to produce calcium phosphate for use in cattle food. As a result, the waste water containing ²²⁶Ra were discharged into two little rivers, one of which is the Laak. The purpose of this study was to chart the radium contamination of the river banks and some areas that are regularly flooded by the river. It was seen that enhanced concentrations of ²²⁶Ra do occur along the river banks, but that the contaminated area is mostly confined to a 10m strip on both sides of the river, even in the flooding zones. At present, no dwellings are present on top of the contamination and no crops for direct human consumption are grown there, so there is no immediate threat to the population.