Strontium Concentrations in Corrosion Products from Residential Drinking Water Distribution Systems.

摘要

The United States Environmental Protection Agency (US EPA) will require some U.S. drinking water distribution systems (DWDS) to monitor nonradioactive strontium (Sr2+) in drinking water in 2013. Iron corrosion products from four DWDS were examined to assess the potential for Sr2+ binding and release. Average Sr2+ concentrations in the outermost layer of the corrosion products ranged from 3 to 54 mg kg -1 and the Sr2 + drinking water concentrations were all < or = 0.3 mg L-1. Micro-X-ray adsorption near edge structure spectroscopy and linear combination fitting determined that Sr2+ was pprincipally associated with CaCO3. Sr2+ was also detected as a surface complex associated with alpha-FeOOH. Iron particulates deposited on a filter inside a home had an average Sr2+ concentration of 40.3 mg kg-1 and the associated drinking water at a tap was 210 Mug L. The data suggest that elevated Sr2+ concentrations may be associated with iron corrosion products that, if disturbed, could increase concentrations above the 0.3 ig L -1 US EPA reporting threshold. Disassociation of very small particulates could result in drinking water Sr2+ concentrations that exceed the US EPA health reference limit (4.20 mg kg-1 body weight).