Journal article
Water Quality of U.S. Drinking Water Kiosks: Lead Release from “Lead-free” Plumbing after Reverse Osmosis Treatment
Environmental science & technology, Vol.60(7), pp.5259-5269
02/24/2026
DOI: 10.1021/acs.est.5c10647
PMID: 41670216
Abstract
Many Americans distrust tap water, leading them to purchase more expensive drinking water sold from water vending machines (e.g., kiosks) that are poorly regulated and sparingly monitored for quality. Here, we analyzed the water quality of 20 kiosks from 4 different manufacturers across 6 states in the first comprehensive comparison of the chemical and microbial characteristics of kiosk water to paired tap samples. Of the 16 kiosks listing specific water treatment processes (others indicated “filtered” or “purified”), only 1 dispensed water with ionic composition (e.g., Na+, Ca2+, Mg2+) inconsistent with the stated treatment. Most kiosks tested used reverse osmosis (RO), which removed fluoride and residual disinfectant, although we found no evidence of microbial contamination. RO also provided the benefit of removing per- and polyfluoroalkyl substances. However, we frequently detected higher lead levels in kiosk water than in nearby tap water. Lead was detected (>0.05 μg/L, our method detection limit) in 15 kiosks; 5 were >1 μg/L (American Academy of Pediatrics recommendation), 2 were >5 μg/L (FDA allowable level for bottled water), and 1 was >10 μg/L (US EPA Action Level). Lead co-occurred with zinc and copper, consistent with corrosion of lead-containing plumbing materials. XRF analysis of plumbing in 2 kiosks from different manufacturers with nationwide distribution confirmed this suspicion although all components in question met the definition of lead free under the Safe Drinking Water Act. Lead release was most evident with the use of RO treatment, which can produce corrosive water low in alkalinity and pH. Going forward, the removal of lead-containing plumbing components downstream of RO treatment and regulation with routine testing of kiosk water quality is imperative to address this unchecked public health risk.
Details
- Title: Subtitle
- Water Quality of U.S. Drinking Water Kiosks: Lead Release from “Lead-free” Plumbing after Reverse Osmosis Treatment
- Creators
- Samantha Zuhlke - University of IowaDrew E. Latta - University of IowaKate Beeman - University of IowaAmukta Gantalamohini - University of IowaJames Kacer - University of IowaGrace Koch - University of IowaDanielle Land - Michigan State UniversityAbby McKeone - University of IowaCasie A. Meyer - Center for Health Effects of Environmental Contamination (CHEEC) University of IowaMatthew R. Nagorzanski - University of IowaAbdul H. Quraishi - University of IowaLilliAnna Scott - University of IowaHanseob Shin - University of Iowa, Hygienic Laboratory - BdcMartin A. St Clair - IIHR-Hydroscience and Engineering, Department of Civil & Environmental Engineering University of Iowa Center for Health Effects of Environmental Contamination (CHEEC) University of IowaDarrin A. Thompson - University of IowaDavid M. Cwiertny - University of Iowa
- Resource Type
- Journal article
- Publication Details
- Environmental science & technology, Vol.60(7), pp.5259-5269
- DOI
- 10.1021/acs.est.5c10647
- PMID
- 41670216
- NLM abbreviation
- Environ Sci Technol
- ISSN
- 0013-936X
- eISSN
- 1520-5851
- Publisher
- American Chemical Society
- Number of pages
- 11
- Grant note
- University of Iowa: NA
Thanks to Benedicte Chubaka, Ted Corrigan, and Melissa Walker for their support to the project. This research was partially supported by the University of Iowa's Center for Social Science Innovation and the Office of Undergraduate Research. The research was performed at the Center for Health Effects of Environmental Contamination at the University of Iowa. Support for the University of Iowa's Center for Health Effects of Environmental Contamination is made available through the Iowa Department of Natural Resources. We thank the manufacturers, owners, and service staff of KI and HP kiosks for their willingness to allow us access to their kiosks for inspection and XRF analysis. The Chemistry Departments of Cornell and Coe Colleges and Dr. Cindy Strong are thanked for their loan of the XRF instrument used in this study. The authors also acknowledge the helpful feedback and recommendations provided by three anonymous reviewers, whose comments greatly improved the quality and impact of this work.
- Language
- English
- Date published
- 02/24/2026
- Academic Unit
- Center for Health Effects of Environmental Contamination; Civil and Environmental Engineering; Occupational and Environmental Health; Hygienic Laboratory - Bdc; IIHR--Hydroscience and Engineering; Center for Social Science Innovation; Chemistry; Chemical and Biochemical Engineering; School of Planning and Public Affairs
- Record Identifier
- 9985139304102771
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