Wow, I was sure you were wrong when I read this but it looks like you're right. Though the reasoning here is a little different from how I interpreted your comm

Wow, I was sure you were wrong when I read this but it looks like you're right. Though the reasoning here is a little different from how I interpreted your comment. It's not that the heaters concentrate minerals by, say, evaporating some of the water, it's that hot water simply dissolves lead from pipes more easily than cold water.https://mobile.nytimes.com/2008/01/29/health/29real.html https://mobile.nytimes.com/2008/01/29/health/29real.html