This all goes back to Erin Brockovich litigating a class action lawsuit in California against PG&E for contaminating drinking water with cancer-causing Hexavalent Chromium.
That was in the 50's and this stuff continues to happen all the time. In fact, it is getting much worse.
Unfortunately, legal fees, lack of available documentation, and no government enforcement are to blame for most of these violations which carry on in secret corporate silence. This is an 'innocent until proven guilty' society, and the onus is on the consumer to demand fair play. The consumer has no legal power or investigative skills, and it takes someone like Erin Brockovich to piece it all together and fight like hell to get somewhere.
When a case is made and won on behalf of the people, the corporations can appeal and carry on legal disputes for decades before anything is done.
The governments and their agencies who regulate water quality do not test for these types of contaminants in your drinking water. It takes a class action lawsuit to find this information. Canada has even lower standards for this kind of behaviour.
Essentially, water can have 50,000 chemicals in it and legally it is 'safe for human consumption' because it passes the low standard of testing performed throughout North America.
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