Interesting comments so far. But I have got to think that there are MANY places in the world where rainwater is still fresh and clean. I really can't imagine that all of the world's rainwater is "poison".

It makes sense that rain is "suspect" if you are downwind (in the path of storms) from major cities with air pollution and industrial pollution.

Rainwater has also been implicated as a potential danger after nuclear explosions (atmospheric), where there is radioactive fallout. For example, the types of tests that were done in Nevada (USA) back in the 1950's. This is because the fallout radiation gets on dust particles. The dust particles are lifted into the atmosphere, and they will be collected when raindrops are condensing in clouds. So scattered "high spots" of radioactivity can occur in the rainfall downwind of an atmospheric nuclear test.

But I would have to think that rain that falls on the coast, from clouds that formed over the ocean, is probably very clean. However - what happens when it falls on your roof, and then flows through the gutter ... that's a good question! Hahahaha!

This topic is not just "random" for me. There's a good chance that I will be moving to a remote location in the next 12 months. And it is very likely that I will be using rainwater as one source of fresh water for drinking and bathing.

Pete