In 1943, Los Angeles residents woke up to air so dark and noxious that they feared the Japanese had launched a gas attack.63 Five years later, a lethal smog in Donora, Pennsylvania, caused by industrial pollutants from zinc-smelting plants and a temperature inversion that trapped toxins in the air64 killed twenty people and sickened thousands.65 In New Hampshire, the Merrimack River, lined with textile mills in Manchester and Nashua, ran in different colors by the day, as dyes and chemicals dumped into the river tinged
