1-DAB, in that respect, there can be no such rule making. Lead, for use in ammo, is explicitly protected by law: Toxic Substance Control Act of 1976, a law in which Congress expressly exempted ammunition.
The EPA can do nothing if the Congress does not repel that section of the law.
The president established a long gun registry specifically in violation of the law in certain SW states via EO did he not? This would appear to violate the FOPA.
We cannot rely on the letter of the law alone to stop EO's. I am not really sure what we do about EO's actually, besides punish the offending party in the midterm elections. What judicial recourse do we have for EO's that violate the law? I think we need to take a wait and see attitude because nothing is going to stop EO's. Its pointless to fret about what could be.