Factors Controlling the Risks of Co-occurrence of the Redox-Sensitive Elements of Arsenic, Chromium, Vanadium, and Uranium in Groundwater from the Eastern United States.

Published

Journal Article

The co-occurrence of contaminants in drinking water may pose enhanced risks to health beyond the effects of single contaminants. Here, we investigated the co-occurrence of four health-relevant redox-sensitive elements (U, As, V, and Cr) in 1494 groundwater wells across North Carolina. The highest concentrations of these elements were measured mostly in groundwater from fractured igneous and metamorphic formations throughout the Piedmont region. Arsenic occurred most frequently in suboxic to mixed redox character groundwater, whereas U, V, and Cr occurred mostly in oxic groundwater. Occurrences of As, and to a lesser extent U, increased with pH, likely reflecting desorption, while higher Cr and V levels were measured in near-neutral pH and oxic groundwater, reflecting greater sensitivity to redox conditions. Due to similar geochemistry, V and Cr co-occurred most frequently. Concentrations of V and Cr(VI) co-exceeded health recommendations from the NC Department of Health and Human Services in up to 84% of wells from the King's Mountain Belt and the Charlotte and Milton Belts of the Piedmont region. This study highlights the large gap between health recommendations and enforceable regulations and demonstrates a degree of co-occurrence between redox-sensitive elements, which may pose additional risks to groundwater-reliant individuals.

Full Text

Duke Authors

Cited Authors

  • Coyte, RM; Vengosh, A

Published Date

  • April 2020

Published In

Volume / Issue

  • 54 / 7

Start / End Page

  • 4367 - 4375

PubMed ID

  • 32167307

Pubmed Central ID

  • 32167307

Electronic International Standard Serial Number (EISSN)

  • 1520-5851

International Standard Serial Number (ISSN)

  • 0013-936X

Digital Object Identifier (DOI)

  • 10.1021/acs.est.9b06471

Language

  • eng