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The extensive school closures due to the unprecedented COVID-19 pandemic resulted in prolonged water stagnation within schools' plumbing for longer durations than routine schools' holidays and summer breaks. With many of the U.S. schools suffering from problems of lead (Pb) in potable water for decades, the extended water stagnation caused by schools' closure has raised significant concerns regarding the schools' water safety. Thus, this research was conducted to evaluate the resiliency of schools' potable water plumbing toward the interruption caused by the COVID-19 pandemic. For this purpose, the impact of extended water stagnation on heavy metal release into water samples collected from fixtures with and without known lead problems in 25 schools within a school district in Tennessee was investigated. The results revealed a significant increase in the median Pb concentration due to the extended water stagnation. Furthermore, elevated levels of Fe, Zn, and Cu were released from both problematic and nonproblematic fixtures into tap water. Estimation of children's blood lead level (BLL), assuming the consumption of prolonged stagnated water, revealed an increased risk of elevated BLLs (>5 μg dL −1 ). To better identify the potential sources of lead release within schools, a combination of plumbing investigation and sequential water sampling was conducted. The lead-containing fixtures, connecting plumbing, and interior plumbing were found as the possible sources contributing to the lead release into water. Implementation of remediation actions reduced the lead release into tap water to less than 3.4 μg L −1 in the target fixtures.
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A Critical Review on the Factors that Influence Opportunistic Premise Plumbing Pathogens: From Building Entry to Fixtures in Residences
Residential buildings provide unique conditions for opportunistic premise plumbing pathogen (OPPP) exposure via aerosolized water droplets produced by showerheads, faucets, and tubs. The objective of this review was to critically evaluate the existing literature that assessed the impact of potentially enhancing conditions to OPPP occurrence associated with residential plumbing and to point out knowledge gaps. Comprehensive studies on the topic were found to be lacking. Major knowledge gaps identified include the assessment of OPPP growth in the residential plumbing, from building entry to fixtures, and evaluation of the extent of the impact of typical residential plumbing design (e.g., trunk and branch and manifold), components (e.g., valves and fixtures), water heater types and temperature setting of operation, and common pipe materials (copper, PEX, and PVC/CPVC). In addition, impacts of the current plumbing code requirements on OPPP responses have not been assessed by any study and a lack of guidelines for OPPP risk management in residences was identified. Finally, the research required to expand knowledge on OPPP amplification in residences was discussed.
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- Award ID(s):
- 2027049
- PAR ID:
- 10406594
- Date Published:
- Journal Name:
- Environmental Science & Technology
- ISSN:
- 0013-936X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1021/acs.est.2c04277
