this post was submitted on 10 Nov 2025
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Today I Learned (TIL)
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Any heavy metals will accumulate in your water heater and the hot water could potentially keep it in suspension. I bet it's worse if you have lead pipes.
Nobody in the last century+ has lead freshwater pipes.
That said, some of our underground infrastructure is very old, and those old iron pipes had fittings sealed with lead and oakum.
Water flowing through such pipes have pH and chemicals carefully controlled to avoid that lead corroding or dissolving. The Flint, Michigan disaster was a direct result of not managing water chemistry correctly, but there are hundreds if not thousands of communities at similar risk who are kept safe by water scientists and engineers doing their job correctly.
That said, hot water tanks do accumulate minute quantities of undesirable metals over time, and depending on a wide variety of variables between the water source and your tap it could result in unhealthy levels of things you don't want to consume.
So yeah, don't cook or drink from the hot water tap.
At least here in Germany lead pipes were only forbidden in new houses after 1973. For old houses they should be replaced by January 2026.
That's not totally true. I've personally removed lead pipes from houses that were built in the 1940s to 1960-1961. They stopped that shit sometime in the '50s or very early '60s here in the US, depending on the state. So it would be true that no house built in the last 65-75 years would have lead pipes, any old houses that have been sitting empty for the last few decades may actually still have some lead pipes.
Well damn. Lead restrictions weren't Federal law until 1986. TIL.
https://www.epa.gov/sdwa/use-lead-free-pipes-fittings-fixtures-solder-and-flux-drinking-water
Although some areas added local restrictions starting in the 1920's, industry lobbies kept the things on the market for decades. Ugh.
https://pmc.ncbi.nlm.nih.gov/articles/PMC2509614/