HONG KONG – Pollution from Chinas export manufacturers is traveling across the Pacific Ocean to reach the U.S. West Coast, according to a paper published in the Proceedings of the National Academy of Sciences.
The study is the first to quantify pollution reaching the West Coast from the Chinese manufacturing sector that produces products from mobile phones to televisions for global export, according to a statement about the study from the University of California Irvine, where one of the authors is based.
Los Angeles sees at least one extra day a year of smog that exceeds federal limits because of nitrogen oxides and carbon monoxide emitted by Chinese factories producing for export, the analysis found.
Chinas economic ascent has been accompanied by a surge in pollution. The World Bank estimates that the Asian nation has 16 of the worlds 20 most-polluted cities.
Weve outsourced our manufacturing and much of our pollution, but some of it is blowing back across the Pacific to haunt us, said Steven Davis, a co-author of the study and an earth system scientist at the University of California Irvine.
Given the complaints about how Chinese pollution is corrupting other countries air, this paper shows that there may be plenty of blame to go around, he said.
Winds called the westerlies can drive airborne chemicals across the ocean and lead to dangerous spikes in contaminants, according to the universitys statement.
Dust, ozone and carbon may collect in valleys in California and other Western states, it said, while noting that China still isnt responsible for the lions share of pollution in the U.S.
China is the worlds largest emitter of anthropogenic air pollutants, according to the paper, with a fraction of its emissions caused by the manufacture of goods for foreign consumption. Anthropogenic pollutants typically refer to those originating from human activity.
On some days, the export-related Chinese pollution contributed to as much as 24 percent of sulfate concentrations over the western U.S., according to the study.