By sending test samples to a lab on a regular basis. The results are on the web page of your county/water supplier. Depends on the country you’re from I guess, but that should be your first place to check.

I kill myself. If I have learned anything from books and movies, it’s that you don’t fuck with time travel.

Nobody seems to have watched it, but “Counterpart”. It’s a mind fuck Science Fiction show. Only 20 episodes, so manageable.

It was cancelled, but the writers knew beforehand and wrote an absolute perfect conclusion for the last episodes.

Also it’s best to go in blind. There are events predicted in the show that later happened for real (I don’t want to spoil it), and it’s fun to think “oh that is how and why it happened”!

Also J.K. Simmons. https://en.wikipedia.org/wiki/Counterpart_(TV_series)

I can’t recommend this show enough.