As if it's not enough that the U.S. is already inundated with goods manufactured in China, now polluted air coming directly from China are invading U.S. shores. And, ironically, the air wafting towards U.S. shores are from factories that manufacture all the goods that are being shipped to the U.S. regularly.
The study, which was published in the Proceedings of the National Academy of Sciences, researched on the quality of U.S. air and found that air pollution in China that is related to its production for exports does contribute the sulfate pollution of the air over certain regions of the US.
Led by Jintai Lin, a professor in the Department of Atmospheric and Oceanic Sciences at Peking University's School of Physics, the study explained that over the past decade, production of goods for export has grown by 390 percent, and has been one of the key drivers of rapid economic growth in China. This massive growth has caused a major change in the structure of the entire Chinese economy. It has turned China into a large net exporter of energy-intensive industrial products, which needs massive energy to support and allow it to grow.
"International trade affects global air pollution and transport by redistributing emissions related to production of goods and services and by potentially altering the total amount of global emissions," the study said. "The US outsourcing of manufacturing to China might have reduced air quality in the western United States with an improvement in the east, due to the combined effects of changes in emissions and atmospheric transport."
The study revealed that Chinese air pollution that is directly caused by production of goods for export contributes a maximum of 12 to 24 percent of sulfate pollution in the western U.S. everyday, although there was a decrease in sulfate pollution in the eastern part of the U.S. In 2006, 36 percent of anthropogenic sulfur dioxide, 27 percent of nitrogen oxides, 22 percent of carbon monoxide, and 17 percent of black carbon emitted in China were associated with the production of goods for export. Black carbon, which has been linked to asthma, lung disease, emphysema, cancer, and heart disease, is not easily cleared from the air by rain.
This transport of export-related Chinese pollution contributed 0.5 t o1.5 percent of ozone over the western U.S. Although polluted air from China isn't the only contributor to pollution in U.S. air, westerly winds can send chemicals across the Pacific Ocean in a matter of days. Valleys and basins in the western parts of the U.S. can also accumulate dust, ozone and carbon. Because of this, the Los Angeles area and many regions in the U.S are already in violation of the U.S. ozone standard one extra day per year.
However, the benefits of outsourcing manufacturing to China still outweigh the risks they present to American public health. The study mentions that because the eastern states of the U.S. have a higher population density than the western states, health hazards affect less people.
"Consideration of international cooperation to reduce trans-boundary transport of air pollution must confront the question of who is responsible for emissions in one country during production of goods to support consumption in another," the study's authors concluded.
"Pollution from China is having an effect in the U.S., and we need to recognize how that is affecting both our background ozone levels and also particulates that are reaching the West Coast," said study's co-author Don Wuebbles of University of Illinois at Urbana-Champaign.
Since air pollution apparently does not respect national boundaries and rules on the use of air space, the study's authors suggest that the countries re-examine the management of energy production, and improve the efficiency of manufacturing processes.
