Material matters: Galvanic corrosion of lead pipes causes increased lead in drinking water

A study, conducted by the Washington University in St. Louis (WUSTL), was prompted by concerns that health safety programs initiated by water utilities in the United States, which use copper pipes to replace the utility's portion of lead drinking water service pipes, may actually increase the risk of lead exposure for water customers. The research shows that galvanic corrosion resulting from new copper pipes coupled with existing lead pipes that have been in service for many years can dramatically increase the amount of lead released into drinking water supplies. During galvanic corrosion, when the oxidation-reduction reaction occurs on the lead pipe, an oxidized species of elemental lead, lead +2, is formed as scale. This is the reason of the increase in the amount of lead in the Lead +2 is much more soluble than elemental lead and more readily leaches into the water. Two ways of chlorinating water to disinfect include using free chlorine, which is essentially bleach, or they use chloramines, which are basically composed of bleach combined with ammonia (NH₃).