Most of the sources I've seen say less than 200 becquerels per litre, where the accepted drinking water limit is 10,000. This article for example says 190 Becquerels.

To say it's not possible to estimate is untrue. An international agency determined it would be within accepted safe limits. Still, one can never know and less is certainly better when it comes to radiation.

Yeah sure let's just make up numbers. Goofy.