Strangely, I think I would be more okay with this than a longer lasting chemical- TP is predominantly lignin, of which the atmosphere already has the constituen

Strangely, I think I would be more okay with this than a longer lasting chemical- TP is predominantly lignin, of which the atmosphere already has the constituent elements. Only worry is stray chlorine, lead and other heavy metal contaminants absorbed into the source material from trees as they grew- but presumably the TP would offset whatever shenanigans those get up to. Since it would break down and burn up upon reentry (or maybe just float down?) there might not be that much interaction anyway. Compare that with the unknowns of longer-lasting particulates of sulfur and other nasties, the back-of-the-napkin math really doesn't sound that bad.