Air you could see, water you could smell.
"By the 1960s, the damage to the natural world from the dramatic economic growth of the postwar era was becoming impossible to ignore," historian Alan Brinkley wrote. Water pollution had grown so widespread that "almost every major city was dealing with the unpleasant sight and odor, as well as the very real health risks, of polluted rivers and lakes."1
In Cleveland, the Cuyahoga River — choked with petroleum waste — actually caught fire from time to time, beginning in the 1950s. In Los Angeles and Denver, weather forecasters began reporting smog levels — a new word built from "smoke" and "fog" — that rose through the day, blotted out the sun, and made people sick.
Pesticides, especially the chemical DDT, were sprayed freely on suburbs, farms, and forests. Songbirds disappeared. The "spring without voices" that Rachel Carson described in Silent Spring (1962) was not a metaphor for many Americans — it was last April.