Gies Business study shows many more die of smoke than of fires themselves

Images from the devastating Los Angeles County wildfires and news of the death toll resonate around the globe. Though the events may seem distant, many people across the country could be physically impacted severely from those fires.

A study out of the University of Illinois Gies College of Business details the health risks posed by smoke plumes that have traveled across the country in the days following wildfires. The study, “The Nonlinear Effects of Air Pollution on Health: Evidence from Wildfire Smoke,” led by Gies researchers David Molitor and Nolan Miller and the University of Michigan’s Eric Zou, looks at wildfires from 2007-19. Its results show that smoke plumes cause more than 191,000 emergency room visits and about 10,000 premature deaths annually among those aged 65 and over. Many of those smoke plumes come from fires hundreds if not thousands of miles away.

The study integrates more than 14.7 million daily remote sensing observations from every county in the United States via NASA’s hazard mapping system (HMS), ambient air pollution data from the Environmental Protection Agency’s (EPA) Air Quality System, and reports from Medicare. The National Bureau of Economic Research published the results.

“Contrary to popular belief, the effects of wildfire smoke are not confined to the areas right around the fire,” Miller noted.  “Due to wind patterns, much of the impact of wildfire smoke exposure occurs far from the fires themselves, including around here.  Many areas of the Midwest have more annual days of smoke exposure than they experience in California.”

For example, most of Illinois gets more than 40 days of smoke annually.

“Sometimes that smoke is high up in the atmosphere, but it often reaches ground level even thousands of miles from its source. It makes for beautiful sunsets but can also signal harmful air quality,” said Molitor.

With data from HMS, the researchers were able to determine both the presence and intensity of smoke plumes. Then they used the EPA Air Quality System to measure its effects on air pollution concentrations. Using Medicare beneficiary data, they calculated how much ER visits and mortality rates increased from their norm during and after smoke events. Molitor noted that the EPA values each life loss at roughly $10 million, meaning those smoke related deaths total $100 billion annually.

The study also measures the impact of wildfire smoke in terms of life years lost. The researchers estimated that the deceased, based on age and preexisting conditions, had an average of 3.5 years of life remaining. That means that wildfire smoke costs older Americans 35,000 life years annually (the average Medicare beneficiary has an estimated 11 years of life remaining).

“The mortality costs of wildfire smoke are substantial,” Molitor noted. “When people think about wildfire costs, they often focus on fire suppression and property damage—substantial losses typically bore by a small group. However, the broader health impacts—over 10,000 premature deaths and nearly 200,000 extra emergency room visits among older adults annually—create a much larger economic burden, but because these costs are spread across the whole country, they’re often overlooked.”

The study also noted that while the impact of thicker plumes was greatest, it wasn’t as significant as the difference between small -to medium-sized plumes.

“The reasons behind this could be because of a biological response, where our bodies’ defense mechanisms kick in at certain thresholds, or it could be a behavioral response, where once the plumes reach a certain thickness, we take notice and adjust our plans and activities,” Molitor speculated. “While we know poor air quality clearly affects health, we’re still understanding exactly how individuals can better protect themselves from harms.”

While interest in wildfire smoke elevated in 2023 as smoke from the Canadian wildfires reached the Midwest and East Coast of the United States. In addition to burning more than 45 million acres, the fires contributed to poor air quality in both Canada and parts of the United States, with smoke drifting across large regions and affecting public health. Molitor, along with more than a dozen colleagues – including Miller - have been leading research in the health and economic impacts of extreme weather for some time through Gies’ Health Care Research Initiative (HCRI). The Congressional Budget Office cited their results in its report, “The Risks of Climate Change to the United States in the 21^st Century.”

“For this study, we started out trying to understand which parts of the country gets exposed to wildfire smoke,” Molitor said on the idea for the study. “When we started this research, I assumed wildfire smoke mainly affected the West Coast and Canada. But the data showed us that smoke doesn’t stay local—it fundamentally changed my understanding of who’s at risk.”

Researchers at HCRI have previously reported the economic impact of illnesses due to smoke events. Molitor believes that much like urban smog 40-50 years ago spurred EPA air quality regulations, perhaps this and other studies will impact air quality standards. He hopes they also heighten awareness of air quality going forward, including encouraging indoor air filtering systems and more preemptive actions. This could not only improve health outcomes but also have significant economic implications. While it is easier to detect the short-term impacts of these measures, some positive health outcomes won’t be able to be identified until years later.

“Health directly impacts workplace productivity,” Molitor notes. “When employees are not well, they aren’t as productive at work. Investing in cleaner air could yield significant economic returns by keeping our workforce healthier.”

How does health care impact business? Can companies effectively incentivize employees to live healthier lives in order to save money in the long run? How does where you live and work impact how healthy you are? In this episode of The Gies Download, Tim Sinclair sits down with Associate Professor of Finance, Director of Gies' Health Care Research Initiative, and Conrad W. and Shirley A. Hewitt Fellow and Deloitte Scholar David Molitor. David and his team are studying the effects of health on business and, so far, the results are extremely surprising.