We all deserve to breathe clean air. Yet, air pollution is the greatest environmental health risk of our time. It can impact us all because air pollution has no boundaries or borders. Air pollution causes 6.7 million premature deaths every year worldwide. Toxic air can cause cancer, stroke, obesity, diabetes, and heart and lung disease. Air pollution is a public health emergency. It can warm the planet, making the climate crisis worse. Air pollution causes huge economic burdens. It harms food and agriculture production. We need individuals, institutions, and governments to take action to ensure clean air for all.
What causes air pollution?
Air pollution is the contamination of indoor and outdoor environments. Chemical, physical, and biological agents can cause air pollution. There are many common sources of air pollution. Some of them are:
- burning fossil fuels
- power generating plants
- commercial manufacturing and chemical production
- construction and demolition
- agricultural pesticides and fertilizers
- cooking or heating appliances
- emissions from internal combustion engines (cars, planes, buses)
- smoke from wildfires
- ash and gases from volcanic eruptions
- methane from decomposing matter
- fine particulate matter
- volatile organic compounds (VOCs)
How can I tell if the air where I live is safe to breathe?
The US Environmental Protection Agency (EPA) shares outdoor air quality using the Air Quality Index (AQI). This is a daily report. It measures five major air pollutants that the Clean Air Act regulates. The EPA sets national standards for each of these pollutants to protect public health. It gathers real-time information using measurements from hundreds of air monitors across the US. They use algorithms to convey hourly readings for specific areas based on this data.
The EPA rates air quality using a color and number scale based on the level of concern. This allows the general public to check their outdoor air quality. You can access this information using the EPA’s AirNow desktop or mobile app. Several mobile weather apps also share this information.
The AQI reports on five major air pollutants:
Ground level ozone (O3)
We call his atmospheric gas “smog”. When nitrogen oxides and volatile organic compounds (VOCs) come in contact with sunlight, then the gas reacts and produces ozone. Ozone can travel far distances from its source. Motor vehicles, power plants, industrial facilities, etc produce ozone. High ground level concentrations of ozone can cause health issues. Exposure can cause headaches, shortness of breath, wheezing, and coughing. It can aggravate conditions like asthma and bronchitis. Ozone can increase respiratory infections and lung inflammation. Long term exposure can cause respiratory and metabolic illness. It can impact the nervous and reproductive system. Ozone can cause cancer and heart disease.
Particulate matter (PM including PM2.5 and PM10)
This fine matter accounts for most of the health impacts from air pollution in the US. Particle pollution can occur in buildings. Or it can enter buildings through windows, doors, cracks, and ventilation systems. It can have chemicals including sulfates, nitrates, carbon, and mineral dust.
What creates it? Vehicle and industrial emissions, burning organic matter, and cigarette smoke. Common household activities create particulate matter. Cooking. Burning candles or incense. Woodworking. Metalworking. And many cleaning and disinfectant products. PM can also have biological sources. PM2.5 are tiny airborne particles 30 times thinner than a human hair. People can inhale these deeply into the lungs, and they can enter the bloodstream. PM2.5 can irritate the eyes, nose, and respiratory system. It can worsen existing lung diseases like asthma and COPD. Long term exposure can cause pneumonia, lung cancer, heart disease, and stroke. PM10 are larger particles that include dust, pollen, and mold spores. PM10 can irritate the eyes, nose, and respiratory system.
Carbon monoxide (CO)
CO is an invisible, odorless toxic gas. It’s a byproduct of combustion. What creates this? It’s mainly vehicles and planes with internal combustion engines, gas appliances, home heating elements, charcoal grills, and gas powered equipment. Breathing CO2 reduces your blood’s ability to carry oxygen. Low level exposure can trigger headaches, nausea, dizziness, weakness, and confusion. Regular low level exposure can aggravate heart disease. It may cause permanent mental and physical problems. High level exposure can cause loss of consciousness and death.
Sulfur dioxide (SO2)
SO2 is a toxic gas from sulfur and oxygen. Large facilities such as coal-burning power plants mainly produce SO2. It can blow hundreds of miles away. Exposure can cause wheezing, shortness of breath, and tightness in the chest. Long term exposure can degrade lung function.
Nitrogen dioxide (NO2)
NO2 is a toxic gas from nitrogen and oxygen. Burning fossil fuels produces NO2. It can form indoors from burning wood or gas. It can form outdoors from motor vehicle emissions, oil and gas production, and power generating plants. NO2 inflames the lungs and can cause coughing and wheezing. It increases vulnerability to lung infections. It can also worsen asthma, making attacks more intense and frequent.
The AQI rating scale indicates the level of concern for each of the five major pollutants.
The scale is color-coded. It contains six categories:
- Green = Good. Green indicates an AQI index value of 0 to 50. Air quality is satisfactory. Air pollution poses little or no risk.
- Yellow = Moderate. Yellow indicates an AQI index value of 51 to 100. Air quality is acceptable. But for some people, there may be a moderate health risk. Especially for those who have underlying conditions that make them sensitive to air pollution.
- Orange = Unhealthy for Sensitive Groups. Orange indicates an AQI index value of 101 to 150. This air quality mostly likely won’t affect the general public. But people with lung disease, older adults, and children are at a greater risk from exposure.
- Red = Unhealthy. Red indicates an AQI index value of 151 to 200. Everyone in the general public may experience adverse health effects. Members of sensitive groups may experience more serious health effects.
- Purple = Very Unhealthy. Purple indicates an AQI index value of 201 to 300. This would trigger a health alert. The risk of serious health effects increases for everyone.
- Maroon = Hazardous. Maroon indicates an AQI index value greater than 301. This would trigger an emergency health warning. This will likely affect the entire population.
Other Hazardous Air Pollution
The EPA regulates the emissions of 188 hazardous air pollutants (HAPs) under the Clean Air Act. HAPs are pollutants that can cause cancer or other serious health impacts. These pollutants can damage your immune, reproductive, cardiovascular, and respiratory systems. They can also cause neurological or developmental problems. Humans are not the only living things that air pollution impacts. HAPs can also harm wildlife and may impact the food chain. The EPA works with state, local, and Tribal governments to reduce emissions of HAPs in the environment.
What are Volatile Organic Compounds (VOCs)?
VOCs are chemicals from living organisms. Products and/or processes emit it into the air. In some cases, VOCs are naturally harmful. In other cases, they react with gases or chemicals and become harmful. Like when VOC’s mix with nitrogen oxides and become ozone. VOCs can pollute indoor and outdoor environments. But concentrations of VOCs can be up to 10 times higher indoors.
Many household products produce VOCs. Paints, varnishes, caulks, adhesives, and flooring like carpet or pressed wood. Cleaning supplies and disinfectants, pesticides, air fresheners, aerosols, cosmetics, and deodorants. Gas and wood burning stoves, stored fuels, and gasoline. Tobacco smoke, candles, and incense. Dry cleaned clothing. Arts and crafts supplies like glues, markers, and photographic solutions. Office printers and copiers. All of these sources and more can produce indoor VOCs.
Several other sources can emit outdoor VOCs. Industrial facilities. Oil and gas extraction or processing. Gasoline or diesel emissions. Biomass wood pellet production. Wood burning. Biomass burning is the second largest source of VOC pollutants. This includes wildfires and bioenergy.
Read more about how bioenergy causes air pollution.
Exposure to VOCs can harm your health. VOCs can irritate your eyes, nose, and throat. They can cause breathing difficulty, headaches, dizziness, loss of coordination, and nausea. VOC exposure can damage your liver, kidneys, and central nervous system. Some VOCs can even cause cancer in humans and animals.
How do I measure indoor air quality?
Indoor air is often more polluted than outdoor air. This is a serious concern since on average Americans spend 90% of their time indoors. Polluted air outside can seep into indoor spaces. This can combine with indoor air pollutants. Then you have unhealthy indoor air conditions. Many building codes require smoke and carbon monoxide detectors. But is that enough?
Indoor air pollution monitors are a useful tool. They can give you information about specific air pollutants. They help you understand how safe the indoor air is. However, they don’t work the same as the EPA air monitoring system. They don’t alert you of imminent danger. But they can help you decide to increase ventilation, air filtration, or reduce sources of indoor pollution.
Air Pollution Monitors
Several air pollution monitors are available on the market. Here are some things to consider:
Cost: Air pollution monitors can range from low cost to high cost depending on your budget. But higher cost does not guarantee better performance or reliability.
Capability: Air monitors use one or more sensors to detect and report on specific air pollutants. They can monitor particulate matter or gases. Such as carbon monoxide, carbon dioxide, radon, formaldehyde, volatile organic compounds. They can also monitor environmental elements like temperature and humidity.
Performance: Ideally, you want a monitor that’s both accurate and precise. What affects air monitor performance? Where you place it. How it processes data. Temperature and humidity. Time in use. Also, air pollution monitor performance can degrade over time. Most manufacturers will provide an estimated lifespan before it needs to be serviced or replaced. Pay close attention to this when purchasing.
Most of us can’t control the air quality of the places we work, learn, shop, or recreate in. But we can use low cost air monitoring devices to help us make more informed decisions.
How do I protect myself from air pollution?
Most air pollution is invisible, so it’s hard to know when you need to protect yourself. Check the AQI for your area if you plan to spend significant time working, commuting, or recreating outdoors. Install and regularly maintain smoke and carbon monoxide detectors in your home. Use air monitors to check the quality of indoor air.
You also can take these steps to protect yourself and improve air quality:
Use an appropriate respirator
Is the air quality unhealthy? Do you know you’ll be around air pollution? Wear a respirator. N95, KN95, P100, or full gas masks can prevent toxic air from reaching your lungs. Make sure you have a tight fitting seal when wearing one.
Eliminate or reduce the source
Avoid burning anything indoors. Don’t use heaters, camp stoves, or fuel burning appliances that don’t vent outdoors. Limit the use of high VOC emitting products like paints, pesticides, or air fresheners. Don’t smoke or vape indoors. Choose furniture and materials that are formaldehyde-free.
Increase ventilation
Get fresh air in and dirty air out. If the outdoor air is better than indoor air quality, then open a door or window. Use ceiling fans to improve air flow. Place a portable fan near an open window to draw clean air in and push unhealthy air out. Point the fan away from people. Turn on the exhaust fans in your kitchen or bathroom.
Filter the air
Most HVAC systems have air filters that need to be changed every three months. Use high quality, pleated air filters. Make sure to install them properly and change them regularly. Set the HVAC system fan to the “on” position. This lets the fan run continuously, even when you turn off the cooling or heating.
Consider adding an air purifier. Portable air purifiers with high-efficiency particulate air (HEPA) filters can remove air pollution and improve air quality. Consider the size of the room when purchasing an air purifier. Check HouseFresh, an independent site that tests and rates air purifiers. Or you can build your own Corsi-Rosenthal air filter box. A study from Brown University shows they’re effective at reducing indoor air pollution.
Get organized
The production and burning of gasoline, oil, diesel, and wood causes the worst air pollution. Organize your community to end fossil fuels and large scale biomass. Advocate to transition our economy from endless extraction to nature-based solutions.
Keep forests and wetlands standing
Forests and wetlands clean our air and store climate warming carbon.