I'll again mention the obvious, that concrete water tanks are very common and there is obviously no health risk from these. I drank out of one for 18 years until I moved into the City. My grandmother drank out of concrete water tanks for 72 years before she moved into a retirement village. She is now over 90.
There can be transfer (or leeching) problems with concrete because it is a porous material and there are always provisions such as polymer DPC used when a building (for example) is in contact with a concrete water tank.
However: The water is stored inside the bottle, The PET is no different to a DPC (moisture barrier). What people are proposing is that 'chemicals' (though no-one will say which chemicals) are able to pass through this barrier which is obviously air and water tight.
In this case you store the bottles on what? Are the bottles not going to leech chemicals from these surfaces also. In this way the concrete is a mute point, unless the chemicals that are 'in' this concrete that we make WATER TANKS out of is worse than synthetic carpet or the vast array of other suggestions you'll find on the net.
I've researched and researched, spoken to University Lecturers and I can't find ANY reliable source of information on the matter.
I constantly come across somebody who says "The LA Fire website said:"
Find this person at: http://faculty.deanza.edu/donahuemary/S ... earthquake
Then you check the LA Fire website on disaster supplieshttp://lafd.org/fire-prevention/119-fir ... saster-kit
and, surprise surprise it says nothing of it.
Lastly: If you look on the internet you'll find a million and one studies that says that drinking our of PET is pretty bad for you. So utube preppers are more than happy to recommend storing water in PET when there are literally hundreds of scientific peer reviewed documents that say that you'll get chemicals from the bottle. But then warn you about storing it on concrete.
I would love to know the etymology of this madness...