Asthma affects more than 6% of U.S. children, making it the most common chronic disease in kids nationwide. It’s difficult to isolate any single cause, but one of the most common contributors is air pollution: Studies have shown that breathing air with high levels of fine particulate matter, nitrogen dioxide and other environmental pollutants can increase children’s risk of developing asthma. But it’s been unclear whether long-term, early childhood exposure to ozone, the pollutant that most frequently exceeds U.S. air quality standards, contributes to the disease.����

, a doctoral student at the 91̽��, set out to find a possible link. In a study , Dearborn and collaborators identified a puzzling trend: Children exposed to higher levels of ozone in their first two years of life were significantly more likely to be diagnosed with asthma or wheezing at ages 4-6 — but researchers didn’t observe the increased risk of asthma at ages 8-9.����

While the researchers couldn’t pin down the exact reason, possible explanations include the changing nature of asthma as kids age, which could lead to a drop-off in formal diagnoses, and the influence of other risk factors and pollutants on asthma as children’s lungs grow.��

“It’s a puzzling finding,” said Dearborn, who led the research in the 91̽��Department of Environmental & Occupational Health Sciences. “It’s something we spent a long time trying to consider, and I don’t know if we ever came up with a satisfying answer. But these findings are important. Even if we only see the effects early in life,��there are still all kinds of associated health care costs and stresses for families. There are all sorts of larger contextual factors about having this chronic disease at any point in life.”��

This study relied on data from the (ECHO) program, a federal research project focused on how a wide range of environmental factors affect children’s health. Researchers drew 1,118 participants from six cities, including Seattle and Yakima, who had low-risk pregnancies and completed validated surveys that asked if their children had been diagnosed with asthma or had experienced wheezing.����

Researchers estimated exposure in the first two years of a child’s life using a model developed by co-author , a 91̽��professor of environmental and occupational health sciences, of epidemiology and of medicine. They found that a relatively small increase in ozone exposure — 2 parts per billion — in a child’s first two years of life was associated with a 31% increase in asthma and 30% increase in wheeze at age 4-6 years. Asthma and wheeze risk at ages 8-9 was not found to be associated with their early life ozone concentration.��

Researchers also analyzed how exposure to mixtures of three common air pollutants — ozone, nitrogen dioxide and fine particulate matter (PM2.5) — affected asthma outcomes. In this analysis, ozone stood out.��

“We interpret trends, and what we can conclude from this analysis is that when ozone within the air pollution mixture was higher than about 25 parts per billion, we saw a higher probability of asthma regardless of the concentration of nitrogen dioxide,” Dearborn said. “We found a relationship between ozone and asthma only when fine particulate matter was at or above median concentrations, giving novel evidence that the relationship between ozone and childhood asthma may depend on the concentration of other pollutants, like fine particulate matter.”��

The study’s findings highlight the need for more research into the effects of long-term ozone exposure in early life, Dearborn said. Further study could determine why the increased asthma risk related to ozone is not evident at ages 8-9, and whether it increases again later in childhood.����

In the meantime, Dearborn said, researchers and public health officials should pay more attention to the effects of long-term exposure to ozone.��

“In the United States, ozone regulations only consider a very short time period,” Dearborn said. “We don’t regulate ozone over the long term, and that’s where this analysis fits in. Maybe we should be considering both a short- and a long-term threshold for the regulation of ozone.”����

Other authors are , a 91̽��professor of environmental and occupational health sciences and of pediatrics in the 91̽��School of Medicine; postdoctoral researchers and , research scientist , and clinical associate professor , all of the 91̽��Department of Environmental & Occupational Health Sciences; , a 91̽��professor of biostatistics; , a graduate student in the 91̽��Department of Epidemiology; of Seattle Children’s Research Institute and an assistant professor of pediatrics in the 91̽��School of Medicine; Margaret Adgent and Paul Moore of Vanderbilt University Medical Center; Yu Ni of San Diego State University; Marnie Hazlehurst and Drew Day of Seattle Children’s Research Institute; Ruby Nguyen of the University of Minnesota; Kaja LeWinn of the University of California, San Francisco; and Kecia Carroll of the Icahn School of Medicine at Mount Sinai in New York City.����

This research was funded by the National Institutes of Health’s ECHO-PATHWAYS program; the National Center for Advancing Translational Health Sciences; the National Heart, Lung, and Blood Institute; the National Institute of Environmental Health Sciences; the 91̽��Pediatric and Reproductive Environmental Health Scholars K-12 program; the U.S. Environmental Protection Agency; the 91̽��EDGE Center; the National Institute on Aging; and the Urban Child Institute.��

For more than a century, American cities have been sliced and diced by high-traffic roadways. Interstate highways and��wide arterials are now a defining feature of most metropolitan areas,��their constant flow of cars spewing pollution into nearby neighborhoods. ��

Researchers have only just begun to understand the health risks posed by all that pollution. Long-term exposure to traffic-related air pollution — a complex mixture of exhaust from tailpipes, brake and tire wear, and road dust — has been linked to increased rates of , , and . ��

New research from the 91̽�� suggests those health risks are also seen in people traveling busy roads. found that unfiltered air from rush-hour traffic significantly increased passengers’ blood pressure, both while in the car and up to 24 hours later.��

“The body has a complex set of systems to try to keep blood pressure to your brain the same all the time. It’s a very complex, tightly regulated system, and it appears that somewhere, in one of those mechanisms, traffic-related air pollution interferes with blood pressure,” said , a 91̽��physician and professor of environmental and occupational health sciences who led the study.����

An by Kaufman’s lab found that exposure to diesel exhaust fumes increased blood pressure in a controlled environment. The roadway traffic study was designed to test that finding in a real-world setting by isolating the effects of traffic-related air pollution.��

Researchers drove healthy participants between the ages of 22 and 45 through rush-hour Seattle traffic while monitoring their blood pressure. On two of the drives, unfiltered road air was allowed to enter the car, mirroring how many of us drive. On the third, the car was equipped with high-quality HEPA filters that blocked out 86% of particulate pollution. Participants did not know whether they were on a clean air drive or a roadway air drive.��

Breathing unfiltered air resulted in net blood pressure increases of more than 4.50 mm Hg (millimeters of mercury) when compared to drives with filtered air. The increase occurred rapidly, peaking about an hour into the drive and holding steady for at least 24 hours. Researchers did not test past the 24-hour mark.����

The size of the increase is comparable to the effect of a high-sodium diet.��

“We know that modest increases in blood pressure like this, on a population level, are associated with a significant increase in cardiovascular disease,” Kaufman said. “There is a growing understanding that air pollution contributes to heart problems. The idea that roadway air pollution at relatively low levels can affect blood pressure this much is an important piece of the puzzle we’re trying to solve.”��

The findings also raise questions about ultrafine particles, an unregulated and little-understood pollutant that has become a source of growing concern among public health experts. Ultrafine particles are less than 100 nanometers in diameter, much too small to be seen. Traffic-related air pollution contains high concentrations of ultrafine particles. In the study, unfiltered air contained high levels of ultrafine particles, though the overall level of pollution as measured by fine particle concentration (PM 2.5) was relatively low, equivalent to an AQI of 36.����

“Ultrafine particles are the pollutant that were most effectively filtered in our experiment – in other words, where the levels are most dramatically high on the road and low in the filtered environment,” Kaufman said. “So, the hint is that ultrafines may be especially important [for blood pressure]. To actually prove that requires further research, but this study provides a very strong clue as to what’s going on.”��

Traffic-related air pollution is the main cause of air quality variation from community to community in most U.S. metropolitan areas.��

“This study is exciting because it takes the gold-standard design for laboratory studies and applies it in an on-roadway setting, answering an important question about the health effects of real-world exposures. Studies on this topic often have a challenging time separating the effects of pollution from other roadway exposures like stress and noise, but with our approach the only difference between drive days was air pollution concentration,” said , a former 91̽��postdoctoral fellow in the Department of Environmental and Occupational Health Sciences and lead author of the new study. “The findings are valuable because they can reproduce situations that millions of people actually experience every day.”��

This research was funded by the U.S. Environmental Protection Agency and the National Institutes of Health.����

Other authors are , , , and of the 91̽��Department of Environmental and Occupational Health Sciences; of the 91̽��Department of Civil and Environmental Engineering; and of the Department of Biostatistics.��

For more information or to reach the researchers, contact Alden Woods at acwoods@uw.edu.

For humans, the early days of the COVID-19 pandemic were a stressful time, marked by fear, isolation, canceled plans and uncertainty. But for birds that inhabit developed areas of the Pacific Northwest, the reduction in noise and commotion from pandemic lockdowns may have allowed them to use a wider range of habitats in cities.

A new 91̽�� led by reports that many birds were just as likely to be found in highly developed urban areas as they were in less-developed green spaces during the peak of the COVID-19 lockdowns. The paper was published Aug. 11 in the journal Scientific Reports.

“Our findings suggest that some birds may have been able to use more spaces in cities because our human footprint was a little lighter,” said Sanderfoot, who completed the study as a doctoral researcher in the 91̽��School of Environmental and Forest Sciences and is now a postdoctoral scholar in the Department of Ecology and Evolutionary Biology at the University of California, Los Angeles.

“For about half of the species we observed, neither land use nor canopy cover had an effect on their site use. That’s very interesting, because we would expect that whether a habitat was mostly covered in concrete or vegetation would tell you something about what birds would be there,” Sanderfoot said.

In the spring of 2020, Sanderfoot and colleagues recruited more than 900 community scientists in the Pacific Northwest to participate in the study. The volunteers chose their own monitoring sites — mostly backyards and parks where they could safely comply with public health orders — and recorded the birds they observed over a 10-minute period at least once a week. This community science approach allowed the researchers to gather data despite the lockdowns and gave many volunteers a welcomed distraction from the stresses of the pandemic.

“I am loving being a part of this!” said Nadine Santo Pietro, a study volunteer, in a written comment as part of the project. “I signed up to observe once a week for 10 minutes but it has become so much more than that. … I am learning so much! And it’s given me something positive to focus on during this strange time we are in right now.”

Volunteer Elaine Chuang wrote: “Being involved not only as a survey participant, but also as a mentor gives me a role in bringing greater appreciation of birds and nature in general to the community at large.”

Among the 35 species that showed the strongest changes in behavior were some of the Pacific Northwest’s most iconic, including black-capped chickadees, great blue herons, downy woodpeckers and Wilson’s warblers. The researchers focused on 46 bird species overall, which were observed by the study volunteers during more than 6,000 individual surveys.

In order to compare the volunteers’ bird observations to human activity, Sanderfoot and her colleagues used data from Google’s Community Mobility Reports, which track the relative amount that people moved around at various points during the pandemic. While most people spent spring of 2020 isolated in their homes, many began venturing out again over the course of the study period.

As people returned to public spaces and human activity increased, the study volunteers recorded an increase in sightings of several bird species. Because they were mostly monitoring in parks and backyards, which tend to be more heavily vegetated, provide more canopy cover and offer more resources for birds than other areas in cities, this could indicate that these green spaces are an important refuge for urban birds.

“The birds may have been elsewhere at the height of the lockdowns, because human activity wasn’t as much of a disturbance, but then returned to those vegetated areas as the activity increased again,” Sanderfoot said. “This could tell us how important it is to build green spaces into our cities. That’s the biggest takeaway for me.”

Other co-authors are , a professor in the 91̽��Department of Environmental and Occupational Health Sciences, and , an associate professor in the 91̽��School of Environmental and Forest Sciences.

This research was funded by the National Science Foundation Graduate Research Fellowship Program and the McIntire-Stennis Cooperative Forestry Research Program from the USDA National Institute of Food and Agriculture.

For more information, contact Sanderfoot at osanderfoot@g.ucla.edu, Kaufman at joelk@uw.edu and Gardner at bg43@uw.edu.

Press release written by Will Shenton, 91̽��College of the Environment.

The newly elected members from the 91̽��are Patrick Heagerty, professor of biostatistics, School of Public Health; Dr. Joel Kaufman, professor of environmental and occupational health sciences and epidemiology in the School of Public Health and of general internal medicine in the�� 91̽��School of Medicine; and Sean Sullivan, dean and professor of the 91̽��School of Pharmacy and professor of health services in the School of Public Health. In addition, David Eaton, dean and vice provost emeritus of the ����’s Graduate School, was recognized for outstanding service.

“Recognitions such as these from the National Academy of Medicine highlight the excellence of our faculty and leadership across the 91̽��,”��said��Mark Richards, Provost and Executive Vice President for Academic Affairs.��“I congratulate our newest members elected to the academy for their demonstrated contributions to the field of health and their ongoing work toward better outcomes for all.”

Heagerty��was recognized��for his development of novel statistical models for longitudinal data to better diagnose disease, track its trajectory, and predict its outcomes. He has revolutionized how dynamic predictors are judged by their discrimination and calibration and has significantly advanced methods for randomized controlled trials.

Kaufman earned��recognition for his international leadership in understanding the health effects of ambient air pollution. His research integrates the disciplines of epidemiology, clinical investigation, exposure science��and toxicology. He was among the first to establish and elucidate the surprising link between air pollutants and cardiovascular disease through acceleration of atherosclerosis.

Sullivan was cited for��pioneering U.S. guidelines for evidence-based drug formulary development. With insurers, he created the value-based formulary product and was the first health economist to serve on global respiratory guidelines (asthma and COPD) panels incorporating economic considerations into recommendations.

Eaton was awarded the��Academy’s��, which is given to a member who has demonstrated distinguished leadership as chair of a study committee or other such activity, showing a commitment substantially above and beyond the usual expectations. A��member of the Academy��since 2011, Eaton is a leader in environmental health research and policy.

Beginning with his participation on the Board on Environmental Studies and Toxicology from 1996��to��1999, Eaton has chaired three consensus study committees, been a member of five others��and served as reviewer and review coordinator of several other projects. Most notably, under his leadership, the Committee on the Review of the Health Effects of Electronic Nicotine Delivery Systems authored an impactful report in 2018 on the public health consequences of e-cigarettes that is still cited widely today.

As a committee chair, Eaton is known for encouraging camaraderie among committee members, allowing for collective thinking to evolve while balancing the need to bring ideas into a cohesive report, helping facilitate agreement among members by drawing them back to the evidence��and bringing together the talents and expertise of all involved to the final product.

Dr. Douglas Paauw honored for teaching by American College of Physicians ��

, 91̽��professor of general internal medicine in the School of Medicine and director of the 91̽��Medical Student Program, has been awarded the by the , a national organization of internists.

The award, established in 1969 and renamed for its first woman , is given annually to a fellow or of the college “who has demonstrated the ennobling qualities of a great teacher.” Paauw was a master of the college in 2009.

He joined the School of Medicine faculty in 1988 and is a physician at the 91̽��Medical Center’s general internal medicine and virology clinics. Paauw also received distinguished teaching awards from the 91̽��in 1997 and from its School of Medicine four times. He is the UW’s Rathmann Family Foundation Endowed Chair in Patient Centered Clinical Education.

Paauw will receive the award at the college’s annual convocation ceremony in April 2020 at the Los Angeles Convention Center.

* * *

Dr. Joel Kaufman named new editor-in-chief of environmental health journal

, 91̽��professor of environmental and occupational health sciences, medicine and epidemiology, has been named the new editor-in-chief of the journal .

The journal is published by the National Institute of Environmental Health and Sciences, which is part of the National Institutes of Health.

Kaufman is a practicing physician who has published more than 200 research papers and review articles on environmental science. Since joining the 91̽��faculty more than two decades ago, he has maintained a research program that encompasses epidemiology, inhalation toxicology, clinical medicine and exposure sciences. He previously served as interim dean for the School of Public Health.

Day-to-day operations for the journal will be carried out by full-time staff under Kaufman’s direction. The journal now enables its editor-in-chief to continue conducting research and teaching at their home institution.��

Kaufman has served on editorial boards and peer review panels for many of the leading clinical medicine and environmental health journals. He previously served on the editorial review board, then as an associate editor, of Environmental Health Perspectives before taking over as interim dean of the School of Public Health in 2016. .

* * *

Allen School faculty members honored by Association for Computing Machinery, Institute of Electrical and Electronics Engineers ��

The , or ACM, has professors and of the Paul G. Allen School of Computer Science & Engineering as among 58 new , honored for their “far-reaching accomplishments that define the digital age.”

Also, the , or IEEE, has named Allen School professor as among its Smith also has an appointment with the Department of Electrical & Computer Engineering.

These announcements bring to 24 the number of current or former Allen School faculty members made an ACM Fellows, and 16 who have been named IEEE Fellows.

* * *

Sam Luboga of Department of Family Medicine to lead Ugandan education commission

, a 91̽��clinical associate professor in the Department of Family Medicine has been named to lead the of The Republic of Uganda. Luboga is also an associate professor of health sciences at , in Kampala, Uganda. The appointment calls for Luboga to lead the nation’s civil service teacher’s personnel board, responsible for ensuring the high caliber of Uganda’s teaching workforce.

“I will make sure that the reputation of the Education Service Commission remains high and grows more,” Luboga said in an about his appointment.

Air pollution — especially ozone air pollution which is increasing with climate change — accelerates the progression of emphysema of the lung, according to a led by the 91̽��, Columbia University and the University at Buffalo.

While previous studies have shown a clear connection of air pollutants with some heart and lung diseases, the new research published Aug. 13 in JAMA demonstrates an association between long-term exposure to all major air pollutants — especially ozone — with an increase in emphysema seen on lung scans. Emphysema is a condition in which destruction of lung tissue leads to wheezing, coughing and shortness of breath, and increases the risk of death.

“We were surprised to see how strong air pollution’s impact was on the progression of emphysema on lung scans, in the same league as the effects of cigarette smoking, which is by far the best-known cause of emphysema,” said the study’s senior co-author, , 91̽��professor of environmental and occupational health sciences and epidemiology in the School of Public Health.

In fact, the researchers found, if the ambient ozone level was 3 parts per billion higher where you live compared to another location over 10 years, that was associated with an increase in emphysema roughly the equivalent of smoking a pack of cigarettes a day for 29 years. And the study determined that ozone levels in some major U.S. cities are increasing by that amount, due in part to climate change. The annual averages of ozone levels in study areas were between about 10 and 25 ppb.

“Rates of chronic lung disease in this country are going up and increasingly it is recognized that this disease occurs in nonsmokers,” said Kaufman, also a professor of internal medicine and a physician at 91̽��School of Medicine. “We really need to understand what’s causing chronic lung disease, and it appears that air pollution exposures that are common and hard to avoid might be a major contributor.”

The results are based on an extensive, 18-year study involving more than 7,000 people and a detailed examination of the air pollution they encountered between 2000 and 2018 in six metropolitan regions across the U.S.: Chicago, Winston-Salem, N.C., Baltimore, Los Angeles, St. Paul, Minnesota, and New York. The participants were drawn from the Multi-Ethnic Study of Atherosclerosis (MESA) Air and Lung studies.

“To our knowledge, this is the first longitudinal study to assess the association between long-term exposure to air pollutants and progression of percent emphysema in a large, community-based, multi-ethnic cohort,” said first author , an assistant professor of epidemiology and environmental health at the University at Buffalo who conducted the research as a postdoctoral researcher at the UW.

The authors developed novel and accurate exposure assessment methods for air pollution levels at the homes of study participants, collecting detailed measurement of exposures over years in these metropolitan regions, and measurements at the homes of many of the participants. This work in the study was led at the 91̽��. While most of the airborne pollutants are in decline because of successful efforts to reduce them, ozone has been increasing, the study found. Ground-level ozone is mostly produced when ultraviolet light reacts with pollutants from fossil fuels.

“This is a big study with state-of-the-art analysis of more than 15,000 CT scans repeated on thousands of people over as long as 18 years. These findings matter since ground-level ozone levels are rising, and the amount of emphysema on CT scans predicts hospitalization from and deaths due to chronic lung disease,” said , professor of medicine and epidemiology at Columbia University who led the study and is a senior author of the paper.

“As temperatures rise with climate change,” Barr explained, “ground-level ozone will continue to increase unless steps are taken to reduce this pollutant. But it’s not clear what level of the air pollutants, if any, is safe for human health.”

Emphysema was measured from CT scans that identify holes in the small air sacs of the participants’ lungs, and lung function tests, which measure the speed and amount of air breathed in and out.

“This study adds to growing evidence of a link between air pollution and emphysema. A better understanding of the impact of pollutants on the lung could lead to more effective ways of preventing and treating this devastating disease,” said , director of the Division of Lung Diseases at the , part of the National Institutes of Health.

“It’s important that we continue to explore factors that impact emphysema,” Kiley added, “particularly in a large, well-characterized multi-ethnic group of adults such as those represented by MESA.”

The MESA Air study was funded by the U.S. Environmental Protection Agency.����and MESA Lung Study were funded by the National Heart, Lung, and Blood Institute. The work was also supported by the National Institute of Environmental Health Sciences.

Other co-authors are Carrie Pistenmaa Aaron, Benjamin Smith and David J. Lederer at Columbia University Irving Medical Center;��Jaime Madrigano, Elsa Angelini, Jie Yang, Andrew Laine and Thomas M. Vetterli at Columbia University;��Lianne E. Sheppard, Kipruto Kirwa, Sverre Vedal, Paul D. Sampson and Adam A. Szpiro at the UW; Eric A. Hoffman at the University of Iowa; Patrick L. Kinney at Boston University; Sara D. Adar at the University of Michigan; and Ana V. Diez-Roux at Drexel University.

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For more information, contact Dr. Kaufman at joelk@uw.edu.