Field and laboratory studies were conducted to determine lead release from new end-use plumbing components installed at drinking water sources (primarily fountains) in Seattle (Wash.) Public Schools. Small-volume sequential field sampling results indicated that most of the lead originated in the first 50 mL drawn from the source. Laboratory testing of new end-use plumbing components showed elevated lead concentrations during early exposure. Periodic spikes in lead were attributed to the movement of valves and possible release of metal particulates or dezincification of brass materials. New end-use plumbing components typically had been installed immediately after purchase. Study results helped identify likely sources of lead and develop mitigation measures (such as preconditioning) so that drinking water sources can be used immediately after retrofitting and meet the Seattle school board policy limiting lead concentrations to 10 μg/L.
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