Sea-Tac Airport exposes communities to unique kind of pollution, UW study says

SEATAC, Wash. – Planes landing at Sea-Tac Airport are polluting nearby communities and schools with a unique set of substances, a new University of Washington study confirms.

The two-year project found that ultrafine particle pollution from aircraft landings within a 10-mile radius of the airport expose communities to more pollution over a larger area than toxins from motor traffic.

These particles are 700 times thinner than the width of a single human hair, making them the smallest particles found in air pollution. They’ve also been linked to breast cancer, heart disease, prostate cancer, and a variety of lung conditions.

J.C. Harris lives on a cul-de-sac directly in the flight path of Sea-Tac’s third runway, according to a UW article. The 58-year-old is weary of the potential health effects on his neighborhood, especially since the airport is the eighth busiest in the U.S.

In 2018, the airport greeted 50 million passengers and saw 438,391 takeoffs and landings.

“There’s a line of schools in the path of runway one where kids are out playing,” Harris said. “So, what are they getting exposed to out there?”

UW researchers gathered air samples from a former elementary school south of the airport and a SeaTac Community Center north of the airport. Samples were also collected through mobile monitors mounted on hybrid vehicles driven through 11 routes north and south of the airport throughout 2018 and 2019.

Their findings suggest that roadway air pollution particles are larger and have higher black carbon concentrations, the second biggest contributor to global warming after carbon dioxide. These particles disperse over shorter distances on major roadways, like I-5 and SR 99, and affect nearby residences and buildings.

Whereas aircraft pollution is made up of smaller ultrafine particles and lower black carbon concentrations but tends to cover larger areas and affects more people.

“We can now study the specific health effects of aircraft-related pollution, how different neighborhoods may be affected by it, and specific interventions that could reduce human exposure to these pollutants,” said Michael Yost, co-investigator of the study, in a UW news release. “We hope to work with state and local policymakers as well as affected communities to pursue these questions.”

The Washington State Department of Health is in the process of preparing a comprehensive literature review of potential health effects associated with ultrafine particles.