Release of lead, copper, zinc from the initial corrosion of brass water meter in drinking water: Influences of solution composition and electrochemical characterization

Ching-Hsuan Hsu; Ding-Quan Ng; Yi-Pin Lin

doi:10.1016/j.envpol.2024.124154

Release of lead, copper, zinc from the initial corrosion of brass water meter in drinking water: Influences of solution composition and electrochemical characterization

Environ Pollut. 2024 May 13:352:124154. doi: 10.1016/j.envpol.2024.124154. Online ahead of print.

Authors

Ching-Hsuan Hsu¹, Ding-Quan Ng², Yi-Pin Lin³

Affiliations

¹ Graduate Institute of Environmental Engineering, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei, 10617, Taiwan. Electronic address: r09541104@ntu.edu.tw.
² Department of Environmental Engineering and Management, Chaoyang University of Technology, No. 168, Jifeng E. Rd, Wufeng District, Taichung, 41349, Taiwan.
³ Graduate Institute of Environmental Engineering, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei, 10617, Taiwan; NTU Research Center for Future Earth, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei, 10617, Taiwan. Electronic address: yipinlin@ntu.edu.tw.

PMID: 38750810
DOI: 10.1016/j.envpol.2024.124154

Abstract

Corrosion of brass plumbing materials may lead to metal release and deteriorate the drinking water quality. In this study, the initial corrosion of brass coupon cut from commercially available water meter was investigated. High rates of Pb, Cu and Zn release from the brass coupon were found during the early stage of corrosion (0-5 d) due to general corrosion and galvanic corrosion. The corrosion current density (I_corr) increased and resistance (R_F) decreased during this period indicating that severe corrosion had occurred. In a later stage (5-30 d), a decreased I_corr and an increased R_F were observed due to the development of a denser layer of Pb and Cu corrosion products which regulated the release of soluble Pb and Cu. The release of Zn continued and no significant Zn precipitation was found. Overall, particulate Pb, particulate Cu and soluble Zn dominated in the metal release during the initial corrosion of brass. The release of Pb, Cu and Zn was enhanced by a lower pH. Free chlorine was found to slightly reduce the release of Pb but promote the release of Cu and Zn. The presence of Pb on the brass surfaces was found to alleviate the dezincification process. A conceptual model based on metal release profile and electrochemical characterization was proposed to describe the initial corrosion of brass in typical drinking water.

Keywords: Brass water meter; Dezincification; Drinking water; Lead contamination.