Investigation of the influence of water parameters on galvanic corrosion of lead and the role of orthophosphate in inhibition of lead release in drinking water distribution system

Abstract

Lead contamination in drinking water has raised concerns in many developed cities in recent years. Addition of orthophosphate has been commonly employed to suppress lead levels in drinking water. Its detailed mechanism, however, has not been fully elucidated. Recent cases of lead contamination in drinking water have been found in cities with no lead pipes, suggesting the source of lead to other piping materials such as leaded solders and brass fittings. These findings led to the development of a series of studies involving galvanic corrosion in drinking water and drinking water sampling protocols. In this study, the mechanistic role of orthophosphate in lead release from PbO2 in chloraminated drinking water, the effects of pH, chloride, sulfate, free chlorine, monochloramine and orthophosphate on galvanic corrosion between lead and copper in drinking water and lead release in a simulated premise drinking water distribution system using a modified sampling method were investigated.