First off How much Chinese Toothpaste really comes to US.
Second, American Toothpaste isn't necessarily any better.
The Sodium Lauryl Sulfate I believe is more harmful than the DEG mentioned above. And the Silica added to most toothpaste acts more like polishing grit/rouge - Certainly gets the teeth clean, but should not be used everyday.
Also I wouldn't think FDA would classify Toothpaste as a food - So therefore it doesn't need to conform to the same laws for ingredients/additives...