A lot of people in Los Angeles (and the United States) are poor. So they buy cheap shit. Their cheap shit is made in China. The pollution from making that cheap shit in China floats across the Pacific Ocean and poisons the very same people who later buy and consume that cheap shit.
A study from UC Irvine researchers “is the first to quantify how much of the pollution reaching the American West Coast is from the production in China ofcellphones, televisions and other consumer items imported here and elsewhere,” and has found that “Los Angeles experiences at least one extra day a year of smog that exceeds federal ozone limits because of nitrogen oxides and carbon monoxide emitted by Chinese factories making goods for export.” On non-excessive days, “as much as a quarter of the sulfate pollution” on the West Coast comes from Chinese manufacturing of goods headed for export.