[Symmetry]

And if you're interested in helping people in places that don't have access to these things that salt ionization is almost certainly the thing to work on first.

http://www.givewell.org/international/technical/programs/sal...

As to Flint that does seem to be finally over now, though goodness knows it went on for a distressingly long time.

https://en.wikipedia.org/wiki/Flint_water_crisis#2017