Science Wednesday: China and Global Air Pollution

Each week we write about the science behind environmental protection. Previous Science Wednesdays.

About the author: Julie A. Layshock is a Ph.D. candidate in the Department of Environmental & Molecular Toxicology at Oregon State University. Her work is funded by an EPA Science to Achieve Results (EPA STAR) Graduate Research Fellowship. She is looking forward to a career focused on reducing human exposure to pollutants.

Westerly winds over the Pacific Ocean efficiently carry sea salt and dust from the Gobi Desert to the western United States. Recently, scientists have begun to detect other, less welcome, things in the wind, too: air particles laden with pollutants from fossil fuels.

People from countries around the world cause tons of pollutants to be emitted into the air we breathe. Everything from operating vehicles, to burning coal and natural gas for heat and electricity, and manufacturing and industry activities all contribute to the global transport of air pollution. The contribution this global transport makes to local air conditions is poorly understood, and the impact it makes to human health can not yet be estimated.

That’s where my research comes in.

image of author with clipboardI am working toward answering questions concerning long-distance air pollution and how China might contribute to pollution in the United States. In my travels to China, I have seen first-hand the effects air pollution can have on human health. Understandable questions arise: Can we really quantify the contribution of pollutants from China and determine the how they affect a person in the United States?

I spent several months in China collecting air particles that I can use to compare with ones I have collected in the Pacific Northwest. My goal is to identify specific pollutants arising from en route chemical reactions in the atmosphere. Using the chemical “signatures” of the particles, combined with powerful meteorological and wind mapping models, I aim to distinguish Chinese sources from our locally produced air pollution. In the laboratory, I am also designing toxicity tests using the collected particles and identifying the most toxic combustion byproducts.

The results of my research could provide much needed insight into the global movement of these combustion-derived pollutants that are attached to particles in the air.

Demonstrating that these pollutants are capable of traveling half-way around the world highlights the need to reduce this type of pollution. Alternative energies and creative pollution control techniques are just a few of the directions that could result from my research.

For further information, I can be reached at

Editor's Note: The views expressed here are intended to explain EPA policy. They do not change anyone's rights or obligations. You may share this post. However, please do not change the title or the content, or remove EPA’s identity as the author. If you do make substantive changes, please do not attribute the edited title or content to EPA or the author.

EPA's official web site is Some links on this page may redirect users from the EPA website to specific content on a non-EPA, third-party site. In doing so, EPA is directing you only to the specific content referenced at the time of publication, not to any other content that may appear on the same webpage or elsewhere on the third-party site, or be added at a later date.

EPA is providing this link for informational purposes only. EPA cannot attest to the accuracy of non-EPA information provided by any third-party sites or any other linked site. EPA does not endorse any non-government websites, companies, internet applications or any policies or information expressed therein.