Lake has a bigger surface area than a pool, so does it matter? Not sure nature can cleanse ionic heavy metal.
Pool with a cover is important if you genuinely think this is a concern
Discussion
Exactly this is why I'm in strong doubt camp. Unless they are just sniping pools with Chen trails lol.
And if this was the case all the heavy metals would filter down into the body of water from the surrounding area collecting more. The pool would be a more protected environment.
Strong doubt confirmed.