The study found about one-fifth the pollution emitted into the atmosphere by China comes from manufacturing goods for export to the US and Europe, according to the paper that was published in the Proceedings of the National Academy of Sciences (see graphic).
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, the researchers found. As much as a quarter of the sulfate pollution on the US West Coast is tied to Chinese exports.
While China is not responsible for the majority of pollution in the US, emissions originating from the country are being pushed by global winds known as westerlies across the ocean causing dangerous spikes in contaminants and dust, ozone and carbon to accumulate in valleys and basins in California and other Western states, the researcher say.
Black carbon, which has been lined to a string of health problems including asthma and cancer, is a particular problem because rain doesn’t easily wash it out of the atmosphere, so it lingers over long distances.
An evaluation released earlier this month by the Beijing-based group Institute of Public & Environmental Health found thermal power plants and steel factories in eastern China that share real-time monitoring data are seriously exceeding national pollution discharge limits.
The group’s Blue Sky Roadmap-Atmospheric Pollution Investigation Phase II Report, found a number of large-scale thermal power plants and steel factories in the Shandong and Hebei provinces had emissions that were in serious breach of discharge standards. Some of these enterprises continued to exceed discharge standards even when the local area was experiencing a period of severe pollution.