Are European pipe tobaccos more "natural" than American pipe tobacco?

Gentleman,
Is there any difference in the amount or type of additives (chemical
flavorings, burn accelerants, etc.) used in American pipe tobacco vs.
European tobacco? Is P.G. only used in American blends?

I know that American cigarrettes are full of chemical stuff to flavor
them. Is this true of some classics like Prince Albert?

Thank you in advance.
Preston

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