Well, here’s another reason to say a little prayer for the monsoon.
Wildfire smoke in 2020 may have caused an extra 19,700 COVID infections and 750 deaths in California, Washington and Oregon in 2020.
The conclusion came from a study by a Harvard researcher published in the journal Science Advances.
The study added one more to the growing evidence that air pollution — including wildfire smoke — remains a lethal health risk all across the nation.
The researchers focused on the release of soot particles 2.5 micrometers across, which previous studies have shown remain among the most dangerous elements of smoke, since they can penetrate deep into the lungs. The Environmental Protection Agency closely tracks air pollution — including this type of almost microscopic soot.
The researchers compared COVID cases and deaths in areas subject to the heavy plumes of smoke from the Pacific Northwest’s disastrous string of megafires to COVID cases in similar areas not in the smoke plume. In California alone, 2.5 million acres burned in 2020 — nearly 20 times the total from the year before.
The situation’s likely even worse at the moment, with the Dixie Fire approaching a million acres and the 180,000-acre Caldor Fire forcing the evacuation of Lake Tahoe.
Fortunately, Arizona’s wet 2021 monsoon shut down the wildfire season. A dry winter and hot dry spring started the fire season early, with giant fires forcing evacuations in Globe, Pine, Rim Country campgrounds and communities throughout the state. Some 600,000 acres burned before the monsoon started. California, Oregon, Washington and other western states blew up just as Arizona cooled — prompting the federal government to shift its overtaxed firefighting resources from Arizona to other states.
Most areas in Arizona have gotten a welcome abundance of rain since June 15, the official start of the monsoon.
Payson has received more than 12 inches, which puts us in the top-10 monsoons ever recorded. The wettest monsoon on record remains the 14.5 inches received in 1970. The driest season came in 1979, with a total of 2.9 inches. The 2020 “nonsoon” came close — with just 3.5 inches.
The growing link between wildfire smoke and health problems especially alarming as the Southwest lurches into a new era of megafires, compounded by drought and decades of mismanagement.
Fortunately, a growing body of evidence also suggests that controlled burns outside of the fire season pose a much smaller health risk than the thick, far-reaching plumes of smoke from crown fires. The megafires not only consume far more acres, they also put more soot and toxins in the air per acre burned — and spread the smoke over a much wider area. The prescribed fires do create smoke that drifts into nearby communities, but the fires generally burn on cooler days with less additional air pollution. In addition, the fires burn much cooler — creating less dangerous soot and toxins. That’s important, since a dramatic increase in controlled burns and thinning projects remains the only way to reduce the steady increase in megafires. Better yet, thinning projects that feed the slash and biomass debris into power plants with pollution control smokestacks result in a big decrease in harmful pollutants in developed areas.
The study linking COVID deaths and wildfire smoke underscores the point.
Thick wildfire smoke first damages the cells that make up the hairs on the inside of your nose, which constitute the body’s first line of defense against airborne viruses and toxins. This may pose an especially grave risk with the Delta variant, which causes a viral load in the nose and throat that’s 1,000 times greater than earlier strains.
Moreover, the small soot particles in wildfire smoke can penetrate deep into the lungs. The body’s immune system reacts to the soot particles, mounting a futile defense on the assumption that the particles are bacteria or virus. The immune response causes inflammation, which reduces lung function. As it happens, the COVID virus also causes still poorly understood inflammation responses in the lungs. The immune system reaction to the virus in the lungs helps account for many of the most dangerous side effects of infection. That includes a mysterious inflammatory response in children months after an infection abates, which remains one of the most dangerous side effects of the virus in children.
The researchers studied COVID infections and deaths in 92 counties in the Pacific Northwest that had big fires in 2020. They documented an 11% increase in COVID cases and an 8% increase in deaths, when compared to similar counties without wildfires. They calculated smoke exposures from satellite images of smoke plumes and EPA data on air quality.
They also attempted to take into account other factors that could affect the spread of COVID, including temperature, population, the mobility of the population and pre-fire case rates.
Another study in Reno, Nevada, came to a similar conclusion. That study documented an 18% increase in COVID cases linked to wildfire smoke exposure.
The studies also underscore national and global studies on the health toll of air pollutants of all kinds.
One 2012 estimate put the global death toll from all sources of air pollution at 10.2 million annually — almost five times the known COVID death toll so far. About 62% of those deaths take place in China and India, where many people cook indoors using coal — which generates a lot of small soot particles. Since then, China has substantially cut its air pollution, which has probably substantially reduced the global total. The World Health Organization estimates between 6 million and 7 million people die as a result of air pollution annually.
In the U.S., the Clean Air Act is credited with substantially reducing air pollution — especially in urban areas. One study concluded the number of U.S. deaths due to air pollution has declined from about 104,000 in 1990 to about 60,000 in 2019.
Unfortunately, the dramatic increase in wildfire smoke in the past decade may have cut into those gains.