
What's in Your Tap Water? Contaminants, Filtration, and How to Test It | Johnny Pujol | The Metabolic Link Ep. 91
The Metabolic Link
Why bottled water vs. tap matters
Johnny contrasts bottled and tap water quality and explains regulatory trade-offs using lead as an example.
You could have elevated levels of contaminants like uranium or arsenic in your drinking water—and not know it. Many of these compounds are colorless, odorless, and undetectable without testing.
Johnny Pujol is a water chemist and the founder of Tap Score, a drinking water testing platform supported by a network of roughly 270 specialized laboratories. His path from electrochemistry research to consumer water testing was driven by a simple realization: the chemistry inside what looks like a clear glass of water is far more complex than most people realize.
In this episode, Dr. Dominic D’Agostino and Johnny break down what’s actually in drinking water, how regulatory standards are set, and where they may lag behind emerging research. They also discuss how chronic exposure to certain contaminants may intersect with metabolic health and long-term disease risk.
Johnny also shares insights from Tap Score’s forthcoming research comparing contaminant profiles in unfiltered tap water, bottled water, and filtered tap water.
Questions Answered in This Episode:
- Why does the EPA action level for lead differ from the ideal target of zero?
- Can certain filtration systems introduce unintended issues, like microbial growth, if not properly maintained?
- How can environmental factors like rainfall impact private well water quality?
- What's the difference between a "first draw" sample and a "representative" sample, and why does it matter?
- Is the health risk from showering in contaminated water meaningful compared to drinking it?
- Why do some water tests cost $600 to $800 while others cost a fraction of that?
Understanding your drinking water starts with recognizing the difference between what’s legally permitted and what may be considered optimal from a health perspective. This conversation explores that gap, and what individuals can do to better assess their own water quality.
Learn more here: https://mytapscore.com/
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