Air quality alerts are issued because air pollution can cause both immediate and long-term health effects. Wildfire smoke contains a variety of particles, inluding tiny particulates called PM2.5, which are 2.5 microns in diameter, compared to 50-70 microns for a human hair. These particles are so fine that they can be inhaled deep into the lungs. The PM10 particles are more likely to land on larger surfaces of your airways.
Acute exposure to PM2.5 and PM10 can cause asthma attacks and exacerbations of COPD, and may require emergency room care or hospitalization for control. Most likely to be affected are babies, children, and adults with heart or lung disease.
Long-term exposure to these particulates is associated with worsening lung disease and premature death due to cancer, heart disease, stroke and dementia.
California has been riddled with wildfires, with 6,200 this year alone. Oregon and Washington states are also particularly at risk. Surprisingly, Arizona, Texas, Louisiana, and Florida also suffer an average of 90-111 wildfire smoke days yearly. Last year, uncontrolled fires spread smoke throughout Canada, through parts of the northeastern U.S., causing a hazardous air quality warning in New York City. Air quality alerts extended from Montana to New York and as far south as Georgia. This summer, the upper midwest is more affected by the Canadian fires.
We've known for years that air pollution's effects match that of other disparities. Poor people and city dwellers are more affected, for example, by being closer to polluting highways or factories. In Africa, Southeast Asia, and the western Pacific, where many rely on cookstoves that use wood or dung, rural and poor people are more affected by smoke.
A report from the American Lung Association notes that predominately African American communities suffered a greater risk of premature death from particle pollution. Another study they cite "found that Hispanics and Asians, but especially Blacks, had a higher risk of premature death from particle pollution than whites did," and that this was not due to economic differences.
Another study from Stanford found that Blacks are both more likely to be exposed to air pollution and more likely to die from it. Although rates have improved, Blacks had a higher attributable mortality due to PM2.5.
The first thing is to check the daily Air Quality Index (AQI) forecast to see what precautions you might need.
An extensive guideline about air quality is available at AirNow, "a partnership of the U.S. Environmental Protection Agency, National Oceanic and Atmospheric Administration, National Park Service, NASA, Centers for Disease Control, and tribal, state, and local air quality agencies." There are also sections on how to protect yourself. For educators, there is a sample curriculum for different ages at BreatheEasy.
There are things you can do to reduce your risk from wildfires or other air pollution sources of PM2.5 particles. If you can, stay indoors and make a "clean room" with few windows and no fireplace. Outfit it with HEPA filters -- you can make a DIY Corsi-Rosenthal Box fan filter for ~$100. This filter will also help reduce your risk of Covid-19 infections.
If you have central air conditioning, use a HEPA or MERV 13 or higher fan filter. You should set the air system to recirculate or close the outdoor air intake damper.
The CDC says that if you must be outside where there is wildlife smoke, you should wear a NIOSH-approved respirator, either an N-95 or P-100 mask. They emphasize that cloth or paper masks ("baggy blue" surgical masks will NOT filter out wildfire smoke). KN-95 masks are not quite as effective but have less air leakage than surgical masks. These same N-95s are what most experts recommend to protect yourself from Covid as well.
Masking protects people against a variety of respiratory infections and wildfire smoke and other sources of air pollution. One problem with these personal protections is that various jurisdictions have been proposing mask bans for "public safety." There is no evidence that mask bans make a community safer. Unfortunately, some of these, like the recent bill passed in Nassau County, NY, allow no medical exceptions to prevent acquiring or passing on infections. North Carolina's bill initially had no medical exemptions, but this has been changed. New Jersey State Sen. John Bramnick (R-Union) just proposed such a bill there. (He did not reply to a request for comment). The NJ Star-Ledger Editorial Board noted, "Republicans have been seeking to criminalize face masks even as COVID cases are surging, once again." They added that mask bans are "a threat to personal freedoms, because it leaves it up to the cops to decide whether someone has a legitimate medical reason for wearing a mask at a public gathering.
How will they know that? It's subjective. And based on past experience, we know what that means: Police will disproportionately stop and question Black and brown people, who have also been the most likely to continue wearing masks to protect against COVID-19."
Masks bans have passed in North Carolina and Nassau County. They have been proposed by Mayor Bass in Los Angeles, New York's Eric Adams and Kathy Hochul, and other jurisdictions.
We have recently had >1 million Covid infections and >1000 deaths per week. We have also seen more frequent and volatile wildfires, especially through the West and Canada and can expect that trend to continue. This will disproportionately hurt people with asthma and COPD, or other lung diseases. Yet, we have some people trying to hamstring our response to these public health crises.