Is bentonite clay in edible oil a food safety concern?

Is Bentonite clay residue in RBD edible  oil a concern?  I see more retail stores come up with this in their "restrictive list", but it is used to bleach the oil, but is then filtered. Any articles that proves that the filtering is effective to remove the Bentonite? 

It has GRAS status in the US, assuming that a suitable spec of bentonite is used and "subject to no significant residue" (i.e. not necessarily absolute absence) in food: https://www.accessda...cfm?fr=184.1155

The only significant concern that I recall seeing around it relates to potential impurities in grades that aren't suitable for food use - Pb levels seem to be one of the more common problems.

Certainly there have been cases of businesses selling unsuitable products (IIRC the FDA has issued a few warnings/enforcement letters) and a quick dig around google suggests that some websites are decrying bentonite as dangerous because they've misunderstood the difference between a contaminant and the substance itself.

Nonetheless I could imagine some brand owners / retailers deciding to move away from it, as brand policy does seem to often be guided by public perception rather than rational science ;)

If it were me, I would send a few samples to a lab to do some testing to test whether this filtration is effective in removing the bentonite the oil. That is the best way to be sure. You also should assess levels/toxicity and doses and which are deemed to be safe.