In 24 lines, Yusef Komunyakaa writes with unveiled disgust of the pollution caused by commerce and industrial waste. He clearly condemns the filth and poison that floats in this dreary, swampy area. (As it is a swamp, the waste will hang in the humid air, slowly poisoning the inhabitants.) The "phantom ship" he speaks of is the paper mill, which emits a sulfurous gas; the air smells of rotten eggs (he says it "smells like the world's oldest anger"), and long exposure to this gas causes respiratory problems, as well as eye irritation, even at low levels (higher levels can cause nerve damage).
He is in a taxicab, "interfaced / With a dead phosphorescence." Phosphorescence carries a double meaning here: it is both light that is emitted from something without any discernible source of heat and latent radiation. In the first case, the city he's watching is black and dreary, and the people have been lulled into acceptance; the city's and the people's "phosphorescence" is dead. With the second meaning, he implies that the town is as deadly as though it were radioactive.
At the end, he speaks of
That turn workers into pulp
When they fall into vats
Of steamy serenity.
The workers whose labor produces the pollution collect their paychecks and go about their lives, oblivious to the fact that they are killing themselves.
What Komunyakaa is telling society is that we are destroying ourselves with our own pollution. This poem is a call for us to help ourselves.