In the first 90 days after the Palisades and Eaton fires broke out in January, Cedars-Sinai Medical Center's emergency room was unusually busy.
There were 46% more visits for heart attacks than usual during the same period over the previous seven years. Visits for respiratory illnesses increased by 24%. And unusual blood test results increased by 118%.
These findings were reported in new research published Wednesday in the Journal of the American College of Cardiology. Research part research project documenting the long-term health effects of wildfires joins several recent papers documenting the physical toll of natural disasters.
While other U.S. wildfires have consumed more acres or claimed more lives, the Palisades and Eaton fires were exceptionally dangerous to human health because they burned an unusual mixture of materials: the trees, brush and organic material of a typical wildfire, as well as a toxic mixture of cars, batteries, plastics, electronics and other man-made materials.
According to the authors of the article, there was no precedent for a situation in which so many people were exposed to this type of smoke.
“Los Angeles has seen wildfires before, it will see wildfires again, but the Eaton fire and the Palisades fire were unique in both their size, scope and the sheer volume of material burned,” said Dr. Joseph Ebinger, a Cedars-Sinai cardiologist and first author of the paper.
The team found no significant increase in the total number of visits to the medical center's emergency room between Jan. 7, the day the fires started, and April 7. During that time, the department saw fewer in-person visits for mental health emergencies and chronic conditions compared to the same period in previous years, said Dr. Susan Cheng, director of public health research at Cedars-Sinai and senior author of the study.
The difference was offset by an increase in the number of visits for acute cardiovascular events and other serious sudden illnesses.
The research team also examined the results of blood tests taken from patients presenting to the emergency department for the presence of serious physical symptoms without immediate explanation—such as dizziness without dehydration or chest pain not caused by heart attacks.
Their blood tests returned unusual results, twice as often as in previous years. According to Cheng, these atypical numbers overlap with the entire spectrum of blood tests. “It could be an electrolyte imbalance, a change in protein levels, a change in markers of kidney or liver function.”
The number of unusual test results remained stable over the three-month period, leading the team to conclude that exposure to fire smoke “resulted in some biochemical metabolic stress in the body that likely affected more than one organ system,” Cheng said. “This is what has led to many different types of symptoms affecting different people.”
Joan Casey, an environmental epidemiologist at the University of Washington who was not part of the Cedars-Sinai team, noted that the study showed that the health effects lasted longer than similar studies.
Three months “is a significant time frame to observe an increased number of visits, as most studies looking at emergency care use following wildfire smoke exposure show an increase in visits over a period of about a week,” Casey said. Her own research found a 27% increase in outpatient respiratory visits among Kaiser Permanente Southern California members living within 12.4 miles of burn zones in the week after the fires.
“The Los Angeles fires were such a severe event, involving not only smoke but also evacuations and significant community stress, that the effects may have lasted longer,” Casey said.
Thirty-one people are known to have died as a direct result of injuries sustained in the fires. But the researchers believe that when deaths from diseases worsened by smoke are taken into account, the true toll would be significantly higher.
A research letter published earlier this year in the Journal of the American Medical Association. calculated that there were 440 additional deaths in Los Angeles County between January 5 and February 1. The paper looked at deaths caused by factors ranging from exposure to air pollution to public health disruptions resulting from closures and evacuations.
On Tuesday, the Stanford University team published his forecast Specifically, exposure to fire smoke resulted in 14 deaths that were otherwise undetected.
Wildfire is a major source of fine particle pollution, particles 2.5 microns in diameter or smaller that are small enough to penetrate the barriers that separate the blood from the brain and outer branches of the lungs.
Compared to other sources, wildfire smoke contains a higher proportion of ultrafine particles, small enough to penetrate the brain after inhalation, Casey told The Times. earlier this year. Smoke is linked to a range of health problems, including dementia, cancer and heart disease.
Over the past decade, an increasing number of wildfires in Western states have resulted in emissions sufficient amount of fine solid particles To reverse annual cost improvements under the Clean Air Act and other pollution control measures.
