Abstract
The maximal admissible concentration of lead in tap water enforced in several countries, including the U.S.A., Canada, and the EC countries, was 50 ug per dm3. Lead contamination of drinking water arose from the interaction of plumbosolvent waters with lead components in the distribution system. Control of lead contamination using either pH and alkalinity modifications or orthophosphate dosing was achieved by decreasing the solubility of the solid phase which precipitated on to the internal pipe surfaces. Maximal control required a lead free distribution system. Thermodynamic speciation models proved valuable in understanding lead chemistry in waters that were essentially inorganic. Other water types required experimental analytical techniques. The size distribution of lead might be indicative of the contamination mechanisms. Organic complexation of lead could be evaluated using chelating resins, anodic stripping voltammetry and gel chromatography.