California residents are waking up more and more often to smoke-filled orange skies as wildfires continue to blaze across the state. While the costs of fires are usually measured by property loss and death tolls, a new study highlights the possibly overlooked impact that the fires have on health care costs.
UC Santa Barbara health economist Daniel Cullen used air quality and public health data to estimate the health care costs related to smoke exposure in California from 2012 to 2018.
“When we’re thinking about the cost of fires, it’s not just about the direct costs. There are these other unaccounted-for costs in people’s health not just near the fire, but further away as well,” Cullen told Noozhawk.
He found that with each additional day of wildfire smoke, there was roughly $188,000 in medical expenditures for respiratory and circulatory hospitalizations per county. The total cost of medical expenses related to fire smoke in California totaled $1.3 billion for the six years that he studied.
Cullen was working on his doctorate at UCSB in 2017 when the Thomas Fire ravaged through the hills of Ventura and Santa Barbara counties. Already interested in the intersection of human health and the environment, and watching people wear face coverings in the pre-pandemic days while ash rained from the Santa Barbara sky, Cullen was inspired to look into the effects of those conditions.
“It’s a theme that affected many people in California,” he said. “I was very aware of the impacts of the smoke.”
Cullen found that with each additional day of smoke exposure, there were 11 more respiratory and three more circulatory hospitalizations per day per county, averaged across the six-year time period. The average annual cost of smoke exposure throughout the state was a little less than $200 million, he found.
“This number is going up every year as more fires are getting bigger and hotter and the smoke plumes are lasting for longer periods,” Cullen said.
The study estimates that smoke-related hospitalizations cost about $88 million in 2012, and skyrocketed to $348 million in 2018.
“These health care costs need to be accounted for when we’re thinking about the costs of climate change,” he said. “We have to keep in mind that it’s the entire American West that is facing this issue.”
While this study applies only to California, the costs of the state’s fires reach much farther, he said. Wildfire smoke doesn’t just stay within state lines; it can reach populations much farther because of prevailing wind conditions.
Cullen used hospitalizations as a metric for health care utilization in his study. He then overlaid smoke plume data on county maps and looked at how many days of exposure to unhealthy air quality occurred in each county.
After comparing the health care data with California’s Office of Statewide Health Planning and Development, Cullen multiplied the increased number of respiratory and circulatory cases by the Environmental Protection Agency’s estimate for what an average case costs and adjusted for inflation.
To control for other confounding factors, he compared each county to itself in the same month during the 2012-18 time period.
Cullen found increased hospitalizations for respiratory and circulatory conditions even after the unhealthy air quality conditions dissolved. The lasting impacts suggest that wildfire smoke is not just accelerating illnesses that would’ve happened anyway, according to Cullen.
“It’s not just changing the timing,” he said. “It’s actually increasing the number of cases.”
While the study still has to undergo peer review, if it holds up, it shows another grave consequence of the ever-present wildfires.
“The main takeaway is that there are unaccounted-for costs of wildfires,” Cullen said. “Exposure to wildfire smoke — not even directly next to the fire but far away — increases hospitalizations for respiratory and circulatory diagnoses, and this, in turn, leads to large costs associated with health care.”