LEACHING OF ANTIMONY, CADMIUM, COPPER, LEAD, SILVER, TIN AND ZINC FROM COPPER PIPING WITH NON-LEAD-BASED SOLDERED JOINTS

Studies were done on the leaching of Ag, Cd, Cu, Pb, Sb, Sn and Zn from 95/5 Sn/Sb-, 96/4 Sn/Ag-, 94/6 Sn/Ag-, and 95.5/4.0/0.5 Sn/Cu/Ag-soldered copper pipes into high-purity, tap, and well water samples as a function of standing time in a static test on new plumbing. There was no significant leaching of Ag, Cd, Pb, Sb and Sn from the above solders into the three types of water samples studied. The amount of Cu released from soldered copper pipes was lower than that released from non-soldered copper pipes. The amount of Zn leached from the non-Pb-based solders studied was well below the Guidelines (< 5 mg/1) for Canadian drinking water quality. Since the potential for public health hazard from Pb-based solders in plumbing systems is significant, it is advisable to use these Pb-free' solders.