lead is corroded by alkalis at moderate or high rates, depending on aeration, temperature and concentration. It is attacked, for example, by calcium hydroxide solutions at room temperature, including waters that have been in contact with fresh Portland cement. In view of this, if Portland cement was used to prepare a concrete, the cement hydration reaction resulted in a high alkalinity which is maintained in the pore moisture of the bulk concrete. This alkaline electrolyte has caused the corrosion of a lead shower pan.