The impact of sampling approach and daily water usage on lead levels measured at the tap

WATER RESEARCH

卷:197

Article

Lytle, Darren A.¹  Formal, Casey²  Cahalan, Kelly²  Muhlen, Christy¹  Triantafyllidou, Simoni¹ 

[1] US EPA, Off Res & Dev, Drinking Water Management Branch, Ctr Environm Solut & Emergency Response,Water Inf, 26 W Martin Luther King Dr, Cincinnati, OH 45268 USA

[2] US EPA, Off Res & Dev, Ctr Environm Solut & Emergency Response, Water Infrastruct Div, 26 W Martin Luther King Dr, Cincinnati, OH 45268 USA

关键词: Lead;    Drinking water;    House;    Sampling;    Water usage;   

DOI  :  10.1016/j.watres.2021.117071

来源: Elsevier

【 摘 要 】

There are many sampling approaches available for lead (Pb) in drinking water. Selecting the best ap-proach for its intended use is critical. The objective of this work was to compare water Pb levels col-lected by multiple sampling approaches from a model home plumbing system (HPS) that included an old Pb service line (LSL), as a function of daily water usage. Specifically, flushed, direct LSL, sequential pro-file, random daytime (RDT), first draw, and manual composite samples were compared, and daily water usage rates ranged from 1.4 to 120 gallons/day (5.3-454.2 L/day). Pb levels in water collected directly from the LSL reached equilibrium after 7-15.5 h of stagnation, and approximately 55% of the equilibrium Pb concentration was reached after 2 h. Sequential sampling accurately identified the LSL; however, the peak profile Pb concentrations were a fraction of the Pb measured directly from the LSL. Daily water usage patterns greatly impacted total Pb levels in all water sampling approaches, although manual com-posite and RDT samples were more sensitive to changes. Manual composite and RDT samples were equal to or greater than first draw samples throughout the study, and differences grew larger as water usage decreased. (c) 2021 Published by Elsevier Ltd.

【 授权许可】

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