I don't think that the intention of the poster was to downplay or cover up anything, it seems that this poster is being picked on, and people are trying to make this into some personal, emotional drama.
I think that highlighting that benzene is very apparent everywhere, and not just in the Gulf, is making people aware that just because they are not in the Gulf area, doesn't mean that benzene is not a problem toxin in our environment. Benzene was in the Gulf before the spill, (although in greater concentrations now).
I do think that the Gulf has copped a big dose of this toxin from the spill, and I'm glad to see so many ideas coming out on how to deal with this.
It would be good to concentrate on how to help people who have been exposed to increased levels of this toxin, instead of trying to pick arguments with other posters, this helps no-one.