The Puget Sound Clean Air Agency air quality monitor shows how much particulate matter is in the air in Marysville. (Kevin Clark / The Herald)

The Puget Sound Clean Air Agency air quality monitor shows how much particulate matter is in the air in Marysville. (Kevin Clark / The Herald)

Your backyard bonfire could put those with COVID-19 at risk

New research connects long-term exposure to air pollution with higher fatality rates from the coronavirus.

MARYSVILLE — Even with far fewer cars on the road, a state “stay home, stay healthy” order hasn’t knocked out air pollution in the Puget Sound area.

The Puget Sound Clean Air Agency reports there was about 30% less pollution from emissions on roads in March — but levels of particulate matter in the air, or smoke, are roughly twice the average for this time of year.

Air quality scientists say increased residential burning, like backyard bonfires and yard debris burn piles, is partially to blame for the spike.

According to an air quality monitor in Marysville on the corner of Seventh Street and Quinn Avenue, particulate matter in the air throughout April was about 50% higher than historic levels.

The spike has caught the eye of some Snohomish County officials, who expressed concern about a potential link between air pollution and increased risk of death from COVID-19.

A recent Harvard report analyzed data from 3,080 counties in the United States and found that long-term exposure to higher levels of PM 2.5, a kind of particulate matter in the air, are associated with increased death rates from COVID-19.

Prolonged exposure to air pollution decreases lung function, worsens lung disease, and increases lung infections and asthma attacks, according to the Puget Sound Clean Air Agency.

That means air pollution contributes to conditions that make someone more prone to contracting COVID-19 as well as decreasing the body’s ability to fight off infection.

Breathing in these particles “exacerbates the severity of COVID19 infection symptoms and worsens the prognosis of COVID-19 patients,” according to the Harvard study.

The research is still preliminary — it’s been submitted for peer review and publication in the New England Journal of Medicine.

But the connection is significant enough that it’s spurred health officials to address fixable smoke sources locally.

One potential cause for the spike in pollution is increased residential burning, agency air quality scientist Phil Swartzendruber said.

The Puget Sound Clean Air Agency air quality monitor shows how much particulate matter is in the air in Marysville. (Kevin Clark / The Herald)

The Puget Sound Clean Air Agency air quality monitor shows how much particulate matter is in the air in Marysville. (Kevin Clark / The Herald)

Some folks are burning wood in their homes to try and save on heating bills, he said. Others are taking advantage of time at home and the nice weather to start recreational bonfires.

Quarantine has inspired many to clean up their yards — and then burn the waste.

“People are home and they’re bored and it seems kind of nice out so they think ‘I’m just going to burn it off,’” r said.

Doing so is illegal. Yard waste should be composted, Swartzendruber said.

Burning yard waste is also a potential wildfire hazard.

The spring sunshine has brought over 260 wildfires to the state so far this year, Washington Department of Natural Resources Commissioner Hilary Franz said in a press briefing Thursday.

And a significant number of those fires are started by people burning waste in their yards.

“They are spending time at home, they are getting their yards ready,” Franz said. “And unfortunately, they are starting them on fire in burn piles at an unprecedented number.”

And when COVID-related service changes caused long lines at county transfer stations, people reportedly started to burn their garbage, too.

In April, county councilmember Megan Dunn started hearing reports of residents “illegally dumping and now burning garbage, which is causing poor air quality and putting some populations at risk,” she wrote to county executive Dave Somers in an email.

At the beginning of April, the county solid waste department reduced its services, restricting hours at transfer stations and closing drop-box locations. The same week, solid waste director David Schonhard said they saw an almost 10% increase in customers.

“Some of that was related to people either working from home or being furloughed,” he said. “A lot of, not household garbage, but more project-related. Like people cleaning out their garage or cleaning their yard.”

With the reduced hours at transfer stations, those homeowners could only drop off their waste on Saturdays.

A Marysville air quality monitor shows particulate matter, or smoke, is 50% higher than it normally is this time of year. (Puget Sound Clean Air Agency)

A Marysville air quality monitor shows particulate matter, or smoke, is 50% higher than it normally is this time of year. (Puget Sound Clean Air Agency)

“We had huge lines before we even opened,” Schonhard said.

That’s part of the reason, along with establishing better COVID-19 protections for staff, solid waste reopened transfer stations to households on weekdays starting May 2.

Some curbside garbage pickup services have also made changes that leave residents with more trash on their hands. Waste Management, which serves parts of rural Snohomish County, has stopped picking up bulky items like furniture, appliances and building materials.

Waste Management communications manager Gary Chittim said that’s to ensure physical distancing between employees. Many bulky items require more than one person to pick up.

Wind, rain, clouds, weather patterns and temperatures all also play a role in pollution levels, Swartzendruber said.

During the first week of Inslee’s stay-home order, he said smoke levels shot up during stagnant weather. The levels almost reached federally regulated limits.

That’s something that normally only happens on cold winter nights, when many burn wood fires for warmth. It’s unusual for a sunny spring, Swartzendruber said.

Based on the emerging connection between COVID-19 deaths and air pollution, the Clean Air Agency is asking residents to avoid unnecessary burning.

It’s one thing if a family starts a fire to stay warm, but “we don’t want people to have a recreational fire every night because they’re home and they have nothing else to do,” Swartzendruber said.

Julia-Grace Sanders: 425-339-3439; jgsanders@heraldnet.com.

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