Fingerprinting Lead in Trenton tap water

Abstract

Recent crises of Pb contamination in the tap water of Flint, MI and Newark, NJ have raised concerns about Pb in tap water. Even at low concentrations, any ingestion of Pb is unhealthy and dangerous for humans. Recent studies have demonstrated the benefits of both sequential sampling of tap water and analysis of Pb isotopes to constrain the number of sources of Pb in tap water. This paper will analyze water samples from Trenton, NJ for Pb concentration, 207Pb/206Pb, and 208Pb/206Pb on an ICP-MS. We conclude that 42%, 53%, and 5% of homes studied have one local source of Pb, two local sources of Pb, and more than two local sources of Pb, respectively. There is no relationship between the number of local Pb sources in a home and the geographic location or Pb concentration of the tap water. The range of Pb isotope signatures in the tap water of homes with one local Pb source is smaller than the range of Pb isotope signatures in homes with two or more local Pb sources. Overall, Pb isotope analysis of with sequentially sampled tap water is the most useful method for constraining the number and location of Pb sources in a single home.