An industrial rock crusher, like those in eastern Travis County (Photo by Getty Images)

A new study published by researchers at the Dell Medical School at UT-Austin has found that poorer air quality in Austin neighborhoods with a higher population of color triggers more asthma-related trips to the emergency room for Black and Brown Austinites than white residents.

The link between asthma symptoms and air quality isn’t new, but this study bears out that longer-term trends of more concentrated air pollution in majority-POC neighborhoods make them less safe to live in – something environmental justice advocates have been saying for years.

UT researchers found that despite relatively low air pollution levels within the Austin metro area as a whole, in its higher pollution areas there was a higher incidence of ER visits triggered by asthma symptoms. Areas in East Austin have the highest average concentrations of multiple types of air pollution that come from car exhaust, road dust, manufacturing, and landfills. “This is a critical piece to the puzzle of why Black and Latinx Austinites suffer a greater burden of asthma,” wrote Sarah Chambliss, lead author of the study, in a press release Monday. “We know the placement of highways and industry in East Austin contributes to greater local air pollution, and this research points to the consequences that may have for racial and ethnic health disparities.”

Ahead of I-35’s inevitable expansion, Austin is already reckoning with the dirty legacy of I-35 both as a tool of racial segregation and as a driver of bad health. If the city can figure out where funding will come from, building caps and stitches over the highway to increase green space and connect neighborhoods split in two could mitigate some of the expansion’s worst effects. Per TxDOT’s own estimates, the expansion will increase emissions by more than 50,000 metric tons of carbon dioxide per year.

But tailpipe emissions are only one source of particulate matter – factories, oil wells, construction sites, and rock quarries can contribute as well. And those particles contain different pollutants. Researchers found that fine particulate matter and nitrogen dioxide were concentrated in the urban core and along transportation corridors, and coarse particulate matter and sulfur dioxide were higher in the northern and eastern suburbs in areas with more industrial activity.

Austin and Travis County will have to come up with a plan to reduce that pollution, and soon. A new EPA standard from February has lowered the threshold of particulate matter that constitutes dangerous air quality. Travis County’s levels have stayed the same for the last 14 years, but under this new standard, we have a year before the EPA issues a formal nonattainment designation – our levels are just over the line. Once that happens, city and county officials have about a year and a half to develop a plan with the Texas Commission on Environmental Quality to mitigate that pollution. If they don’t get it under the new limit the federal government can withhold funding for new transportation projects (unfortunately not the I-35 expansion, which is already underway).

By 2032, the EPA hopes required reductions in pollution nationwide will prevent 4,500 premature deaths and result in 800,000 fewer asthma attacks annually. But they’re also not expecting Travis County to succeed in avoiding nonattainment by that year, per a projection published this year along with the new standards.

”These findings underscore the urgent need for targeted interventions to mitigate pollution in neighborhoods with higher asthma burdens, especially where Black and Latinx people live,” wrote Elizabeth Matsui, co-author of the study, in the press release. “By understanding the role of specific urban pollution sources, we can better address the underlying environmental injustices contributing to asthma disparities.”