Butte County Air Quality Management District bldg - Image: courtesty of Butte County Air Management.

Last month, the Butte Environmental Council (BEC) launched the first installment of their 2022 Sustainable Communities and Environmental Justice Community Forum Series. While panelists on the forum shared ongoing air quality preservation efforts in Butte County and its surrounding air districts, it was two pollutants, ground-level ozone, and particulate matter, that took center stage as the primary targets of these efforts to support public health.

“Air pollution is considered the invisible killer,” said Lacey Moore, a member of BEC’s board of directors and one of the forum’s panelists. “According to the World Health Organization, air pollution is responsible for 29% of the deaths by lung cancer, 24% of the deaths from stroke, 25% from heart disease and 43% from lung disease.”

Air pollution, both visible and invisible, occurs when pollutants chemically react to elements in the air and transform into different compounds. 

Every Breath You Take

“Some compounds react to sunlight, causing a chemical reaction to make ozone,” said Moore, referring to a natural and man-made chemical compound made up of three oxygen atoms (O3). “Air pollution can affect air quality further through things like weather and hot temperatures, which might trap air pollutants closer to the ground. These pollutants, in turn, can cause different human and environmental health effects.”

The effects of air pollution on human health are numerous and extensive, particularly if one is exposed to poor air quality conditions over a long period of time. 

“When the air is smoky, you might get a headache, sore throat, cough or skin irritation and these symptoms can become long-term,” Moore said. “Air pollution can affect your central nervous system, causing cardiovascular respiratory diseases that impact all of your organs, blood stream and reproductive systems.”

For current context, Moore cited emerging research from the American Lung Association that found exposure to even small amounts of air pollution over an extended period of time can make someone 8% more likely to die from COVID.

But Moore elaborated with a key distinction when it comes to understanding air pollution and one of its critical pollutants: ground-level ozone. 

For ozone, where it forms determines whether it’s harmful or beneficial to the human population.

The ozone layer in the stratosphere forms a protective layer about 10-25 miles above the Earth’s surface, absorbing most of the sun’s harmful ultraviolet light. But ground-level ozone in the troposphere, the lowest layer of the Earth’s atmosphere, is created by chemical reactions between oxides of nitrogen and volatile organic compounds (VOCs) to form what is considered a greenhouse gas. 

It’s this ground-level ozone that forms the visible haze, or smog, that can be particularly harmful to human and environmental health. 

“Ozone in the troposphere is in the air that we breathe and can reduce lung function by 20%, so we consider ground-level ozone a bad ozone,” Moore said. “It also damages vegetation by inhibiting plants’ ability to breathe by disrupting their photosynthesis. When the amount of carbon dioxide plants can process and release as oxygen is inhibited, this can reduce agricultural crop and commercial forest yields, growth and survivability of tree seedlings and increase plant susceptibility to disease.”

The major air pollutant of concern during wildfire impacts is fine particulate matter, also known as PM2.5. While all persons may experience varying degrees of symptoms, the more sensitive individuals, such as the young, the elderly, pregnant women, smokers, and those with respiratory conditions are of greatest risk at experiencing more aggravated symptoms. These symptoms may include, but are not limited to coughing, watery and itchy eyes, and difficulty in breathing. – Image courtesty of Butte County Air Management.

Aside from ground-level ozone, another key pollutant is known as “Particulate Matter,” or “PM.”

“Particulate matter is a mixture of extremely small particles and liquid droplets in the air, which can be emitted directly from a chemical reaction in air,” Moore said. “PM can enter the atmosphere directly from power plants, factories, vehicles, dirt, roads, wood-burning or even agriculture.”

Particulate matter is so small that a measurement of PM10, means that it’s ten microns in diameter or about a fifth the size of a human hair.

But for as small as it is, particulate matter can have significant implications for human and environmental health.

“Particulate matter can strongly affect our lungs and heart, triggering asthma attacks, heart attacks, and other health problems,” Moore said. “PM can acidify lakes and streams, changing the nutrient balance in coastal waters and large river basins. It can deplete the nutrients and soil, damaging sensitive forests and farm crops, which will affect the diversity of ecosystems and contribute to acid rain that stains and damages our infrastructure.” 

Pollutants like ground-level ozone and particulate matter are the driving forces behind recent efforts to measure and combat their presence in our atmosphere. 

One organization seeking to address the harmful effects of air pollution is the Butte County Air Quality Management District, of which Jason Mandly is the Senior Air Quality Planner and was another panelist in the BEC forum.

“We have ever-expanding air quality sensors monitoring locations throughout Butte County,” Mandly said. “While they are very accurate, they’re also very expensive, so right now there’s only four of them in the entire county- two of which are measuring the ozone. But these new sensors are bringing citizen-science to air quality, which will be important moving forward.” 

While the Environmental Protection Agency establishes air pollution standards and regulations for industries at the federal level, Mandly pointed out that the only other entity that establishes its own standards is the State of California. 

“The California Air Resources Board is the state air quality agency based in Sacramento, California, and established its National Ambient Air Quality Standards (NAAQS), which really guide much of the efforts that we do to meet these air quality standards,” Mandly said. “They also have a huge array of different things like implementing air toxic control measures. If we don’t meet these standards, we have to create new plans, regulations, and more incentives to get us towards meeting these air quality standards.” 

The Butte County Air Quality Management District achieves its objectives by conducting emission inventories to identify sources, providing compliance assistance and implementing enforcement measures for rules and regulations through citations. 

“Our guiding light is to meet air quality standards and avoid pollution exposure for a variety of different air pollutants,” Mandly said. “[Our measures] include rules for fugitive dust, open-burning, public nuisance and visible emissions, even regulation for certain types of coatings to control the volatile organic compounds (VOCs), which facilitate the ozone and the summer smog problem.”

Additionally, they also issue permits for prescribed, agricultural, residential, fire-hazard and open burns to ensure they’re conducted safely and responsibly. 

Aside from these measures, the Butte County Air Quality Management District is also active in public education efforts on the harmful effects of air pollution.  

“The air quality index table is a document that we made with the Butte County Office of Education and the Butte County Public Health and it was sent to all the different school districts in Butte County, offering guidance for managing episodes of wildfire,” said Mandly. 

Butte County group photo – image: courtesy of the Environmental Coalition of Butte County

Public education is also a key proponent for the Butte Environmental Council and its Community Air Protection Education (CAPE) program. 

“We educate Butte County residents of all ages about the impact that air quality has on environmental and human health and the human influence that causes these impacts,” said Juliette Liu, BEC’s education and outreach coordinator. “We empower participants with the knowledge of why it’s important to have healthy air and a sustainable future.”

CAPE workshops not only include formative presentations but in-depth demonstrations that introduce science and its complicated topics to young minds through activities and crafts.

“We also provide take-home materials that students can share with their parents,” Liu said. “The workshops and all of its materials are free of charge and are a great way to convey these really important issues to members of our community.”

Butte County citizen gathering – image: courtesy of the Environmental Coalition of Butte County

From air quality management districts to public education workshops and online community forums like the one hosted by BEC, conversations around the importance of implementing responsible air quality measures are bound to become more prominent as the need for climate adaptation measures continues to develop across the state of California.

Identifying and understanding these pollutants, from ground-level ozone to particulate matter, appears to be the first of many steps toward the state’s climate-responsive future. 


Scott King writes about science and the environment for the Sierra Nevada Ally. He has a Master’s degree in Media Innovation from the University of Nevada, Reno, and a Bachelor’s degree in Professional Writing with a minor in Marketing from Capital University in Columbus, Ohio. Scott served for two years as a literacy instructor with the Peace Corps in the community of Gouyave, Grenada. Support his work.


Founded in 2020, the Sierra Nevada Ally is a self-reliant 501c3 nonprofit publication, a member of the Institute for Nonprofit News, that offers unique, differentiated reporting and explanatory journalism on the environment, conservation, and public policy, and gives voice to writers, filmmakers, visual artists, and performers. We rely on the generosity of our readers and aligned partners.