Water quality sampling, ...

Water quality sampling, analysis, and assessment of potential risks, is still in its infancy and is dependent on testing science that does not include adequate capability to detect a wide range of greywater contaminants.... just because a testing entity states that they have tested for a suite of chemical contaminants does NOT mean that there were not other chemicals in that water that were not tested for... and go undetected.

We have created about 85 thousand chemicals, largely new to the world environment, released as ingredients in products to spread around the world to eventually degrade into water pollution. Many of these have adverse effects potentials at chronic low dose levels that can even be accumulative in nature. Very few are EVER included in actual testing of greywater. You don't often find what you don't look for with a high degree of scientific integrity intent.

As always it is 'buyer beware'. We really know very little about all of the potential chemicals that could be present in any given greywater, we don't even have adequate tests developed to test for them all even if we knew we needed to. We DO NOT do testing that is logically and scientifically sufficient to assert with unfailing confidence the 'safety' of greywater.

We can only say, after our modest testing, that we think that we have done due diligence in testing.... but our inadequacies of testing abilities and assessments remain less than what is scientifically adequate. Politics, and profit margin pressures,  step in to limit the testing process to very little actual analysis. It is all relative, and we DO need to use water at some point, so we just do what testing we usually rely on and let it go at that.... but the real science of it remains hidden behind a screen of what we have not yet learned. Buyer beware.