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Mainland China is the worlds largest emitter of anthropogenic air pollutants, and measurable amounts of Mainland Chinss pollution are transported via the atmosphere to other countries, including the United States.However, a large fraction of Mainland Chinas emissions is due to manufacture of goods for foreign consumption.Here, we analyze the itnpacts of trade-related Mainland Chinas air pollutant emissions on the global atmospheric environment, linking an economic-emission analysis and atmospheric chemical transport modeling.We find that in 2006, 36% of anthropogenic sulfur dioxide, 27% of nitrogen oxides, 22 % of carbon monoxide, and 17% of black carbon emitted in Mainland China were associated with production of goods for export.For each of these pollutants, about 21% of export-related Mainland Chinas emissions were attributed to Mainland Chinato-US export.Atmospheric modeling shows that transport of the export-related Mainland Chinas pollution contributed 3-10% of annual mean surface sulfate concentrations and 0.5-1.5% of ozone over the western United States in 2006.This Mainland Chinas pollution also resulted in one extra day or more of noncompliance with the US ozone standard in 2006 over the Los Angeles area and many regions in the eastern United States.On a daily basis, the export-related Mainland Chinas pollution contributed, at a maximum, 12-24% of sulfate concentrations over the western United States.As the United States outsourced manufacturing to Mainland China, sulfate pollution in 2006 increased in the western United States but decreased in the eastern United States, reflecting the competing effect between enhanced transport of Mainland Chinas pollution and reduced US emissions.Our findings are relevant to international efforts to reduce transboundary air pollution.