Is it true that you can tan more under water?

Ive been a life-long devotee of and visitor to that wonderful country, Mexico. Every foreign visitor is told Don't drink the tap water, it's unhealthy. REALLY? EVERYWHERE, like all over this vast, eco-diverse geography? How can this be true?

• I've unquestioningly obeyed this  edict for lo' these many years. Never mind my nagging  rational doubts about the likelihood of a border-respecting pestilence that says Tijuana tap water is unhealthy while Laredo, Tx water is FINE! OR that says that if I will just stick to drinking only bottled water, any foods prepared for me in public eateries will also have been kept safely away from local tap water too! So This year I tried an experiment. I just returned from six weeks along the Caribbean coast. All but one of my learned water habits I stuck too.  I ate in ordinary restaurants , nowhere high-end. But I brushed my teeth 3X daily using the local tap water. Guess what? I didn't get sick! Don't try to tell me I've gained a tolerance over my many years of travel all over Mexico. I've NEVER ONCE been ill in my many sojourns, eating native-prepared foods in some really "Sloppy Joe"  type diners. My home is in Canada, where PURE water is what we've scads of! No, my pristine GI tract just has NO PROBLEM  with Mexico's water. So is the bottled water business in Mexico just cashing in on a hoaxed-up scare marketing bonanza,? Or WHAT?

• Answer:

  The issue generally in Mexico is the presence of e Coli, a bacteria that causes gringos to get sick. I've been sick there a couple of times when eating in local restaurants in the interior. Other times I have not gotten sick. Treatment standards are much higher and e Coli is a target for removal in the US. I don't service Mexico but you can learn more about treating drinking water at http://www.cleanairpurewater.com