Air quality alerts were in place for 110 million US residents on Wednesday as smoke from Canadian wildfires choked the skies.
New York, Washington DC, Delaware and Pennsylvania had the worst air quality in the nation on Wednesday morning, EPA data showed. Levels in central New York were deemed “hazardous” – the worst level on the EPA’s index for air quality reporting – while Philadelphia was placed under a “code red” as the air quality index soared to its highest level since 2008.
Exposure to smoke can trigger an array of health problems, experts say, but there are ways residents can keep themselves safe.
Staying inside and especially refraining from strenuous outdoor activity is an important way to limit exposure, said Laura Kate Bender, the national assistant vice-president of the healthy air program at the American Lung Association.
If one must go outside, experts suggest wearing a mask – preferably an N95 or equivalent.
Keeping indoor air clean by closing windows and doors is also helpful, as is turning on air purification devices when possible. (The Environmental Protection Agency does not certify air purifiers, but California regulators recommend these models.)
Wildfire smoke is made up of a cocktail of irritants, including gaseous pollutants like carbon monoxide and hazardous air pollutants like polycyclic aromatic hydrocarbons. Most concerning, it can include pollution particles known as fine particulate matter or PM2.5, which are so tiny that they can enter the bloodstream when breathed in.
The smoke can create an array of health problems, including shortness of breath, coughing, wheezing and eye irritation, especially for at-risk groups.
People with asthma, chronic obstructive pulmonary disease, and other respiratory issues are particularly vulnerable, as are children, who breathe in more air because their lungs are still developing.
Pregnant people can have diminished lung capacities, making them more vulnerable to wildfire smoke as well. Exposure to air pollution has also been linked to gestational diabetes, preterm birth and even stillbirth.
Other vulnerable groups include those with a “significant chronic disease”, said Kimberly Humphrey, climate change and human health fellow at the Center for Climate, Health, and the Global Environment at Harvard TH Chan School of Public Health.
“Things like diabetes, heart disease, and heart failure are all aggravated by poor air quality as well,” she said.
Meanwhile, while the west coast has seen a dramatic rise in wildfire smoke over the past decade, for eastern US residents, wildfire smoke can be especially dangerous due to a lack of awareness.
“If you live somewhere where there are frequently wildfires, then people generally are aware of it being an issue and they know what to do,” said Humphrey. “But where there haven’t been significant wildfires or smoke before, we find people often don’t know what to do.”
To stay safe amid the pollution, residents in affected areas should remain aware of local air quality by keeping tabs on local weather and news alerts.
Another helpful resource is the Environmental Protection Agency’s airnow.gov website, which rates air quality on a scale. Levels 0 to 50 are considered the healthiest, levels over 150 can trigger some symptoms, and levels over 200 are considered “very unhealthy”.
But the responsibility to say safe from wildfire smoke cannot only fall on individuals, said Humphrey. Policymakers must also take steps to protect communities.
That’s especially true for lower socioeconomic communities, she said, who may have less access to proper ventilation and effective masks, and may be more likely to work in outdoor settings.
As the climate crisis, driven by the burning of fossil fuels, dries out once wet areas and sends temperatures soaring, wildfires are set to become a more common occurrence across the US.
“The climate is changing, and we know that we will see impacts of wildfires of wildfire smoke where we never saw them before,” said Humphrey. “The key is for our policymakers to really keep ahead of that and to do really adequate risk assessments now, before things get even worse.”