I work for Goodyear and we make several different sizes of those tires at our factory. The Tripletreds use a compound in the sidewall they call 'Permablack". Looking at those tires though I'd have to disagree
Those tires are pretty popular and I'd say probably 75% of the people at the factory have at least one set of Tripletreds and I've not heard of anyone else having that problem. I recently put a set on our 2003 Matrix and there'* another set in the basement for the Bonneville that are going to be mounted this fall.
Couldn't hurt to give customer service a call.