The Scientific Impact of California Wildfires on Air Quality

 The Scientific Impact of California Wildfires on Air Quality

Wildfires have long been recognized for their far-reaching consequences, particularly on air quality. In regions such as California and Australia, these natural disasters have left a distinctive mark on atmospheric conditions over time. Through the lens of scientific inquiry, we seek to comprehensively understand the intricate relationship between California wildfires and air quality.

The Complex Chemistry of Wildfire Smoke

Wildfire smoke, a complex mixture, comprises several essential constituents, as elucidated by the Environmental Protection Agency (EPA). Its composition includes carbon dioxide, water vapor, carbon monoxide, particulate matter, hydrocarbons, organic chemicals, nitrogen oxides, trace minerals, and a myriad of other compounds.

However, within this intricate blend, specific pollutants merit heightened scientific attention. We delve into the primary constituents of concern:

  1. Ultra-fine Particulate Matter (PM2.5): Wildfires produce substantial quantities of ultra-fine particulate matter, predominantly PM2.5 and smaller particles. These minuscule entities, with a size smaller than 2.5 microns, assume a pivotal role in environmental health. Their diminutive dimensions facilitate direct absorption into the bloodstream, affording them access to vital organs such as the lungs, heart, and even the central nervous system.

  2. Volatile Organic Compounds (VOCs): During the combustion of biomass in wildfires, volatile organic compounds (VOCs) are generated. These VOC gases encompass a spectrum of hazardous constituents, including ethane, aldehydes, benzene, toluene, ethylbenzene, xylene, formaldehyde, and acetaldehyde. Inhalation of these VOCs from wildfire smoke bears serious health implications, encompassing irritation of ocular, nasal, and respiratory passages, neurologic sequelae, and an elevated risk of carcinogenesis.

  3. Other Toxic Gases: The milieu of wildfire smoke extends to include a panoply of other toxic gases, notably sulfur dioxide (SO₂), nitrogen dioxide (NO₂), ozone (O₃), and carbon monoxide (CO). These gases assume greater relevance in proximity to the source of the fire, as their concentration tends to be markedly elevated. Carbon monoxide, in particular, commands attention due to its potentially lethal properties.

Air Quality Impacts: A Scientific Lens

Our scientific exploration extends to two geographically distinct regions – Australia and California – to assess the repercussions of wildfires on air quality.

Australia Bushfires: The bushfires that besieged Australia during 2019-2020 engendered adverse air quality conditions, notably in the southeastern states of Victoria and New South Wales. The prominent factor contributing to this phenomenon was the prevalence of ultra-fine particulate pollution, encompassing PM2.5 and PM10, which achieved exceptionally high levels during the apogee of the conflagrations.


California Wildfires 2020: In 2020, California bore witness to one of the most severe wildfire seasons in its history. The concomitant release of wildfire smoke precipitated a deterioration in air quality across the western expanse of the United States. Metropolitan areas, including Portland and Seattle, grappled with hazardous air quality levels. Portland, in particular, attained the ignoble distinction of being ranked as the world's most polluted city in September 2020, an attribution to the injurious air quality stemming from California wildfires.

California Wildfires 2023: As of August  8, 2023, data from the California Department of Forestry and Fire Protection (Cal Fire) denote a significant reduction in the expanse of land consumed by wildfires, signifying a 90% diminishment compared to the conflagrations of 2020. Although the situation exhibits improvement, the specter of wildfires continues to loom ominously.

Scientific Visualization: To afford a quantitative perspective on the influence of wildfires on air quality, a comparative analysis of PM2.5 pollution concentrations is presented. This visual elucidation underscores the escalating severity of pollution levels associated with the increase in particle concentration. Notably, even under adverse conditions, New York City's air quality remains markedly superior in comparison to Portland during the wildfires. However, it is imperative to underscore that Portland's pollution concentration surpassed recommended thresholds by a formidable factor of 47.

Portland vs California Wildfires & Smoke 

In summation, the scientific exploration of wildfires, such as those in California, demands an intricate comprehension of the interplay between the fires and air quality. This multifaceted relationship underscores the importance of scientific inquiry in safeguarding public health during wildfire events.

2020 & 2021 California Mega fires and the devastation they leave behind 


Steve Torbenson CEO & Founder of RZ Mask & RZ Industries LLC