Where did all of the mercury in fish come from? How did it become unsafe in my life time?

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2 months ago

I know it is dangerous, thanks for the links though. How did it get into all of the lakes and oceans over the last 50 years?
http://www.mercuryexposure.org/index.php...

fishing wieghts..chemical plants..people tossing car batteries in lakes..depend where you live.all water leads to the ocean eventually

its all the boats damn the boats