U. researchers find pollution linked to lower student test scores

Math and English test scores tank when dirty air peaks

Winter inversions in the Salt Lake Valley are doing more than harming kids’ lungs. Recent research found spikes in air pollution may also impact their performance at school.

Heaps of scientific studies have connected chronic exposure to fine particulate matter to poor cognition, including in children. But a team of University of Utah scientists looked to the Wasatch Front’s unique pollution problem — periods of stagnant air that cause muck to build up, peak, then dissipate when a storm moves in.

The study looked at third graders’ standardized English and math test scores in Salt Lake County from the 2016-2017 school year. The scientists compared underperforming scores with the worst inversion days, when fine particulate, or PM2.5, was in the 95th percentile for the year. The results showed that lower scores were linked with bad pollution days for all 156 of the county’s primary public schools.

“We couldn’t say definitively that something was a causation, but there absolutely is an association with the statics that we ran,” said the study’s lead author Casey Mullen, a doctoral student in sociology, in an interview.

The researchers selected third graders because they’re in a critical age of brain development and are more sensitive to health effects of air pollution.

They also controlled for students facing social and economic disadvantages, meaning that all children are vulnerable to educational challenges when the valley’s pollution is at its worst, regardless of their race, cultural background, where they live or their family’s wealth.

Interestingly, social disadvantage controls did not show a correlation between lower test scores when kids are exposed to chronic pollution, when bad air quality levels remain steady. Sara Grineski, a professor in the U. Department of Sociology and a co-author of the study, said that’s because social inequality overlaps so tightly with areas of the county experiencing long-term air pollution, particularly on the Salt Lake Valley’s west side.

“Here, we can’t disentangle the effects of school disadvantage ... from the effects of chronic air pollution because they’re happening in the same places,” Grineski said.

The study was published on Sept. 22 in the International Journal of Environmental Research and Public Health. It’s part of a growing body of work that shows how Utah’s unique pollution mix is harming both adults and children. Earlier this fall, for example, another U. study linked air pollution with school absences in Salt Lake City.

“We decided to look at peak exposure because it’s locally relevant and it has been underexamined” in other air quality research, Grineski said. “It allows us to use Utah, and do policy-relevant work in Utah, while also speaking to the broader research community that’s focused on these issues.”

The results further highlight the need for lawmakers to fund air quality solutions in schools, including air filters in classrooms, experts say.

“For whatever reason, a lot of our lawmakers — who are the ones who need this information — seem to be persuaded by local research,” said Brian Moench with Utah Physicians for a Health Environment, who reviewed the study but did not contribute to it. “This kind of research is very consistent with literally hundreds of other studies, so this is not a surprise. But it’s nice to see the [same] conclusions drawn by other studies.”

Some fine particulates can embed in organs like the brain and remain in the body indefinitely, Moench added, harming children irreversibly.

“If a kid arrives at school having inhaled air pollution, he arrives at school with an inflammatory state in [his] brain. Then he’s going to have a tough day at school,” Moench said. “In many circumstances, especially during inversion season, there is never a long enough respite for this inflammatory state to subside.”

The U. study’s authors encouraged lawmakers to take steps to limit students’ exposure to pollution. Legislators could prohibit school districts from building in areas prone to high levels of pollution, retrofit buses and design cities so kids have better routes to schools. They could also make science-informed decisions to update the state’s air quality regulations.

Last month, the U.S. Environmental Protection Agency declared the Wasatch Front “in attainment” for particulate pollution, and will likely end its oversight over Utah’s air quality improvement efforts.

But environmental advocates have accused the EPA of cherry-picking data to reach that conclusion. Other public health experts and scientists have urged regulators to make pollution thresholds stricter.

“We would definitely advocate for that,” Mullen said.

EPA has deemed 35 micrograms per cubic meter of fine particulate its standard for nonattainment. But in the U. study, 23 micrograms per cubic meter was the peak threshold that caused children to struggle with test scores countywide.

“What’s the takeaway from this?” Mullen said. “It’s really, we can all do our parts to ask our legislators to reconsider what regulation standard they will use, especially when air pollution is a particular problem of concern here.”