LOS ANGELES — Extreme heat and wildfire smoke are independently harmful to the human body, but together their impact on cardiovascular and respiratory systems is more dangerous and affects some communities more than others.
A recent study published in the journal Science Advances said climate change is increasing the frequency of both hazards, particularly in California. The authors found that the combined harm of extreme heat and inhalation of wildfire smoke increased hospitalizations and disproportionately impacted low-income communities and Latino, Black, Asian and other racially marginalized residents.
Firefighters watch as the Fairview Fire burns on a hillside Sept. 8, 2022, near Hemet, Calif. Experts say extreme heat and wildfires disproportionately impact low-income and minority communities.
The reasons are varied and complicated, according to the authors from the Scripps Institution of Oceanography at the University of California, San Diego and the UCLA Fielding School of Public Health. Structural racism, discriminatory practices, lack of medical insurance, less understanding of the health damages and a higher prevalence of multiple coexisting conditions are among the reasons.
Infrastructure, the surrounding environment and available resources are also factors. Homes and workplaces with air conditioning and neighborhoods with tree canopy cover are better protected from extreme heat, and some buildings filter smoke from wildfires and insulate heat more efficiently. Areas with access to cooling centers, such as libraries, also offer more protection.
“Even if you’re very susceptible — you have a lot of comorbidities — you may have many opportunities to not be impacted, not being hospitalized, not having to go to the ER, but if you live in a place that is quite remote that does not have access to a lot of social services or amenities, … it may be more trouble,” said Tarik Benmarhnia, a study author and climate change epidemiologist at UC San Diego.
Experts warn that climate change — which is worsening extreme weather events such as droughts, heat waves and wildfires — will increase the frequency and intensity in which they occur simultaneously.
While the study focused on California, similar patterns can be found in other parts of the western United States such as Oregon and Washington state, in parts of Canada including British Columbia, and in regions with Mediterranean climate, said Benmarhnia.
Researchers analyzed California health records — broken down by 995 ZIP codes covering most of the state's population — during episodes of extreme heat and toxic air from wildfires. They discovered that between 2006 and 2019, hospitalizations for cardiorespiratory issues increased by 7% on days where both conditions existed, and they were higher than that in ZIP codes where people were likelier to be poor, nonwhite, living in dense areas and not have health care.
California's Central Valley and the state's northern mountains had higher incidences of both hot weather and wildfires, likely driven by more forest fires in surrounding mountains.
Residents in the Central Valley agricultural heartland are particularly vulnerable to the adverse health effects of both because they are likelier to work outdoors and be exposed to pesticides and other environmental hazards, said Benmarhnia.
Beyond the health risks, being hospitalized has other significant consequences, such as losing hours of work or school, or being left with hefty medical bills.
During extremely hot days, the human body has a harder time cooling itself off through sweating, said Christopher T. Minson, professor of human physiology at the University of Oregon, who wasn't part of the study. The body can become dehydrated, forcing the heart to beat faster, which elevates blood pressure.
“If you’re dehydrated or if you have any kind of cardiovascular disease, … you’re going to be less able to tolerate that heat stress, and that heat stress can become very, very dangerous,” he said.
Some particles found in wildfire smoke can enter easily through the nose and throat, eventually arriving at the lungs, according to the Environmental Protection Agency. The smallest particles can even enter the bloodstream.
The combination of heat and smoke can cause inflammation in the body, Minson said, which is “going to make all your cardiovascular regulation worse, and you’re going to be at even more risk of heart attacks and other problems like long term, poor health outcomes from that. So it’s definitely a snowball effect.”
A 2022 study by the University of Southern California found that the risk of death surged on days when extreme heat and air pollution coincided. During heat waves, the likelihood of death increased by 6.1%; when air pollution was extreme, it rose by 5%; and on days when both combined, the threat skyrocketed to 21%.
When Dr. Catharina Giudice worked at a hospital in Los Angeles, she noticed an uptick of emergency room visits from patients with various health conditions on extremely hot days. When wildfires blazed, she saw more people with exacerbated asthma and other respiratory diseases.
As climate change fuels the intensity and frequency of heat waves and wildfires, Giudice worries about the low-income and minority communities that are less adapted to them.
“For a variety of reason, they tend to feel climate change much worse than other non-underserved communities, and I think it's really important to highlight this social injustice aspect of climate change,” said the emergency physician and fellow at the Harvard T.H. Chan School of Public Health, who was not part of the study.
Climate change fuels disproportionate impact of wildfires on vulnerable
Weslee Chinen looks at the updated death certificate for his wife Sharlene Rabang, who was named as the 100th victim of the Lahaina wildfires, with Rabang's daughter Lorine Lopes, right, Dec. 5, 2023, at his family home in Waipahu, Hawaii. The report made Rabang the 100th victim of the deadliest U.S. wildfire in more than a century. The Aug. 8 fire devastated the onetime capital of the former kingdom of Hawaii. It wiped out an estimated 3,000 homes and apartments in Lahaina as it raced through dry, invasive grasses, driven by winds from a hurricane passing far to the south.
Wilted palm trees line a destroyed property, Friday, Dec. 8, 2023, in Lahaina, Hawaii. A wildfire that tore through the heart of the Hawaiian island of Maui this summer showed how older residents are at particular risk from disasters. Sixty of the 100 people killed in the Maui fire this summer were 65 or older. Many relatives are now facing grief and anger or feeling robbed of final years with their elders. The number of people exposed to natural hazards has increased as climate change has intensified disasters like wildfires and hurricanes. Studies suggest that wildfire disproportionately affects vulnerable people such as those who are older, have a diminished capacity to respond to danger, or are low-income.
Briena Mae Rabang, 10, holds the ashes of her great-grandmother Sharlene Rabang, who was named as the 100th victim of the Lahaina wildfire, while posing for a photo with her father Branden, left, and grandfather Brandon, right, Friday, Dec. 8, 2023, in Kahului, Hawaii. Sharlene's family fought to have her listed as a victim due to smoke inhalation after she died weeks after fleeing the fire. "Me and my mom was really close, we talked multiple times a day," Brandon said.
Briena Mae Rabang, 10, in red, who lost her home in the August wildfires in Lahaina and whose great-grandmother Sharlene Rabang was named as the 100th victim, sits with other children during a toy giveaway at the Church of the Nazarene, Friday, Dec. 8, 2023, in Kahului, Hawaii. Honolulu's medical examiner said a contributing cause of her death was the thick, black smoke that Rabang breathed as she fled. In September, a team of wildfire researchers in the U.S. West found that in the past decade, the number of highly vulnerable people living within the perimeter of wildfires in Washington, Oregon and California more than tripled from the decade before, to more than 43,000. When a wildfire destroyed the town of Paradise, California, in 2018, 68 of the 85 victims were 65 or older, and more than a dozen had physical or mental impairments that impeded their ability to evacuate.
Leis and flowers adorn crosses at a memorial for victims of the August wildfire above the Lahaina Bypass highway, Dec. 6, 2023, in Lahaina, Hawaii. The wildfire that tore through the heart of the Hawaii island of Maui this summer showed how older residents are at particular risk from disasters. Recordings of 911 calls from the Maui wildfire underscored how susceptible older residents were. One woman called about an 88-year-old man left behind in a house: “He would literally have to be carried out,” she told the dispatcher. A man reported that his elderly parents called him after their home caught fire: “They just called to say, ‘I love you, we’re not going to make it.'”
In this photo provided by Lorine Lopes, Weslee Chinen, left, and Sharlene Rabang are shown at their wedding ceremony, Aug. 7, 2021, in Lahaina, Hawaii. Honolulu's medical examiner said a contributing cause of her death was the thick, black smoke that Rabang breathed as she fled. The report made Rabang the 100th victim of the deadliest U.S. wildfire in more than a century.
Lahaina wildfire victim Sharlene Rabang's cat Poke, who she rescued as she fled the Lahaina wildfires in August, sits on a couch at the family home of her husband Weslee Chinen, Tuesday, Dec. 5, 2023, Waipahu, Hawaii. Honolulu's medical examiner said a contributing cause of her death was the thick, black smoke that Rabang breathed as she fled. The report made Rabang the 100th victim of the deadliest U.S. wildfire in more than a century.
The Rev. Ai Hironaka, resident minister of the Lahaina Hongwanji Mission, walks through the grounds of his temple and residence destroyed by wildfire, Thursday, Dec. 7, 2023, in Lahaina, Hawaii. A wildfire that tore through the heart of the Hawaiian island of Maui this summer showed how older residents are at particular risk from disasters. Sixty of the 100 people killed in the Maui fire this summer were 65 or older. Many relatives are now facing grief and anger or feeling robbed of final years with their elders.
Photos of Sharlene Rabang, who was named as the 100th victim of the Lahaina wildfires after dying weeks after fleeing her home, Tuesday, Dec. 5, 2023, are seen at her husband Weslee Chinen's family home in Waipahu, Hawaii. Honolulu's medical examiner said a contributing cause of her death was the thick, black smoke that Rabang breathed as she fled. The report made Rabang the 100th victim of the deadliest U.S. wildfire in more than a century.
Weslee Chinen, whose wife Sharlene Rabang was named as the 100th victim of the Lahaina wildfires after dying weeks after fleeing their home, pets Sharlene's adopted cat Poke, who was rescued from the fires, Tuesday, Dec. 5, 2023, at his family home in Waipahu, Hawaii. Rabang, who had a previous history of cancer, COVID and high blood pressure, was not originally listed as a victim until her family fought to have her included, citing smoke inhalation as a contributing factor. Chinen was in Oahu at the time of the fires, and Rabang's son Brandon had to convince her to flee.
Lahaina wildfire victim Sharlene Rabang's cat Poke, who she rescued as she fled the Lahaina wildfires in August, sits on a couch at the family home of Rabang's husband Weslee Chinen, Tuesday, Dec. 5, 2023, in Waipahu, Hawaii. Honolulu's medical examiner said a contributing cause of her death was the thick, black smoke that Rabang breathed as she fled. The report made Rabang the 100th victim of the deadliest U.S. wildfire in more than a century.
Weslee Chinen, whose wife Sharlene Rabang died weeks after fleeing their Lahaina home during the August wildfire, holds up a stack of melted bowls he recovered from their destroyed home, Tuesday, Dec. 5, 2023, at his family's home in Waipahu, Hawaii. Rabang, who had a previous history of cancer, COVID and high blood pressure, was not originally listed as a victim until her family fought to have her included, citing smoke inhalation as a contributing factor. Chinen was in Oahu at the time of the fires, and Rabang's son Brandon had to convince her to flee.
A copy of Sharlene Rabang's death certificate updated to include smoke inhalation due to the Lahaina wildfire is pictured, Tuesday, Dec. 5, 2023, at her husband Wesley Chinen's family home in Waipahu, Hawaii. Rabang, who had a previous history of cancer, COVID and high blood pressure, was not originally listed as a victim until her family fought to have her included, citing smoke inhalation as a contributing factor. Chinen was in Oahu at the time of the fires, and Rabang's son Brandon had to convince her to flee. The report made Rabang the 100th victim of the deadliest U.S. wildfire in more than a century. The Aug. 8 fire devastated the onetime capital of the former kingdom of Hawaii. It wiped out an estimated 3,000 homes and apartments in Lahaina as it raced through dry, invasive grasses, driven by winds from a hurricane passing far to the south.
Photos of Sharlene Rabang, who was named as the 100th victim of the Lahaina wildfires after dying weeks after fleeing her home, Tuesday, Dec. 5, 2023, are seen at her husband Weslee Chinen's family home in Waipahu, Hawaii. Rabang, who had a previous history of cancer, COVID and high blood pressure, was not originally listed as a victim until her family fought to have her included, citing smoke inhalation as a contributing factor. Chinen was in Oahu at the time of the fires, and Rabang's son Brandon had to convince her to flee.
A photo of Louise Abihai is tied to a fence at a memorial for victims of the August wildfire above the Lahaina Bypass highway, Wednesday, Dec. 6, 2023, in Lahaina, Hawaii. The wildfire that tore through the heart of the Hawaii island of Maui this summer showed how older residents are at particular risk from disasters. Sixty of the 100 people killed in the Maui fire this summer were 65 or older.
Leis and flowers adorn crosses at a memorial for victims of the August wildfire above the Lahaina Bypass highway, Wednesday, Dec. 6, 2023, in Lahaina, Hawaii. The wildfire that tore through the heart of the Hawaii island of Maui this summer showed how older residents are at particular risk from disasters. Sixty of the 100 people killed in the Maui fire this summer were 65 or older.
Photos of victims are seen placed under white crosses at a memorial for victims of the August wildfire above the Lahaina Bypass highway, Wednesday, Dec. 6, 2023, in Lahaina, Hawaii. The wildfire that tore through the heart of the Hawaii island of Maui this summer showed how older residents are at particular risk from disasters. Sixty of the 100 people killed in the Maui fire this summer were 65 or older.
Cars pass by a memorial for victims of the August wildfire, Wednesday, Dec. 6, 2023, above the Lahaina Bypass highway in Lahaina, Hawaii. The wildfire that tore through the heart of the Hawaii island of Maui this summer showed how older residents are at particular risk from disasters. Sixty of the 100 people killed in the Maui fire this summer were 65 or older.
Zaevah Erickson-Castaneto, 7, does a cartwheel while being followed by sister Mahina, 2, as they return to their room at the Honua Kai Resort & Spa, where the family currently lives after being displaced by the August wildfire Friday, Dec. 8, 2023, in the Kaanapali area of Lahaina, Hawaii. The children's great-grandmother Louise Abihai was among the victims in the deadliest U.S. wildfire in more than a century that took the lives of at least 100 people and destroyed most of the historic town of Lahaina.
Erika Erickson, whose grandmother Louise Abihai died in the August wildfire, moves an air mattress in her family's room at the Honua Kai Resort & Spa, where they currently live after being displaced, Friday, Dec. 8, 2023, in the Kaanapali area of Lahaina, Hawaii. While the family has been told they can stay until early next year, "the tricky part is, you still don't know if you might get a call (to move)." The deadliest U.S. wildfire in more than a century took the lives of at least 100 people and destroyed most of the historic town of Lahaina on the Hawaiian island of Maui.
Kailani Amine, whose great-grandmother Louise Abihai, 97, died in the Lahaina wildfire in August, works at a makeshift desk of her boxed-up belongings Tuesday, Dec. 19, 2023, at her home in Seattle. Amine, who moved to Seattle in 2020 to work on her masters degree, is moving back to Hawaii to be closer to her family after the tragedy.
FILE - Rev. Ai Hironaka, resident minister of the Lahaina Hongwanji Mission, offers a prayer inside the nokotsudo, or columbarium, that survived being destroyed by wildfire, Thursday, Dec. 7, 2023, in Lahaina, A wildfire that tore through the heart of the Hawaiian island of Maui this summer showed how older residents are at particular risk from disasters. Sixty of the 100 people killed in the Maui fire this summer were 65 or older. Many relatives are now facing grief and anger or feeling robbed of final years with their elders.
The tide circulates around rocks as it rises at Wahikuli Wayside Park on Nov. 3, 2023, in Lahaina, Hawaii. A wildfire that tore through the heart of the Hawaiian island of Maui this summer showed how older residents are at particular risk from disasters. Sixty of the 100 people killed in the Maui fire this summer were 65 or older. Many relatives are now facing grief and anger or feeling robbed of final years with their elders.
