This is what's "particularly striking"? There's only one substantial class of people who would knowingly live near extreme pollution: people who can't afford to move away. The most trivial of logic dictates that if anyone is living near extreme pollution, there's a substantial probability they're poor.
Now, that said, news about this new study saying that the problem is bad that quantifies the problem, tells us why it's worse than these EJ scholars suspected, or even just a reminder that this is bad and these peoples' lives should be improved, sure, go ahead... but the above statement of shock detracts from that, I should think.