I can remember two times in my life where I’veencountered water-quality issues.
One was in Ireland about a decade ago when one of the towns we spent the night in had a boil order in effect. The hotel provided plenty of distilled water for guests. The other was on my first business trip to the Far East where I was cautioned beforehand not to drink the water. So what do I do in the hotel the first morning? Start to run my toothbrush under the sink. Luckily I caught myself before toothbrush met water.