AWWA WQTC64121

A 12-month study of six commercially available residential brass kitchen faucetswas conducted to determine total and particulate lead and selenium leaching at variousstagnation times as well as continuous long-term simulated residential use at the PortlandWater Bureau's Water Quality Laboratory. The faucets were selected to representvarying lead content and included one faucet manufactured with Envirobrass, a brassalloy with a lead content of less than 0.25%.A test of varying stagnation times found that the Envirobrass faucet and one otherfaucet had no detectable lead in 1-L samples for stagnation times as long as six hours,while the maximum lead concentration in the samples of the other faucets were found tobe 2 µg/L, substantially lower than the 15 µg/L action level.Afterwards, a sequential sampling plan of four 60-mL samples and one 760-mLsample was used to monitor the long-term changes in lead release from the faucets. Theresults of the four small initial samples were compared with a separate destructivemetallurgical analysis of duplicate faucets to identify specific internal faucet componentsthat were releasing lead. The final 760-mL sample was used to obtain an aggregate 1-Lsample. The maximum initial lead release from the faucets was calculated between 1 - 2µg/L in the aggregated 1-L sample, with most faucets having lead release between aneven lower 0.1 and 1 µg/L. For some faucets, very low, but detectable, lead was detectedin each of the 60-mL samples, indicating that low amounts of lead was present in most, ifnot all, of the interior metal faucet components. For other faucets, including theEnvirobrass one, the very low lead release was isolated to only one or two parts of thefaucet that contained lead. The remaining faucet components had no lead and thereforedid not contribute to any lead in the sampled water.The results also found that identical faucet lead release varied by a factor ofnearly two and that the Envirobrass faucet leached lead at very low, though detectable,concentrations. Finally, continuous use of the faucets found slowly decreasing leadrelease due to the long-term passivation of the faucet interiors.Selenium release from the Envirobrass faucet was found to be 0.6 µg/L or less inall samples, significantly less than the 50 µg/L MCL. Includes abstract only.

Product Details

Edition:

Vol. - No.

Published:

11/01/2006

Number of Pages:

2

File Size:

1 file , 300 KB