Air Pollutants and Health Effects

Particulate Matter

Particulate Matter, or “soot,” is made of microscopically small particles, either solid or liquid. The smaller the particles, the deeper they can penetrate into the respiratory system, which causes more significant health problems.

Particles less than 10 micrometers in diameter can cause significant health problems. Particles under 2.5 micrometers, called “fine” particles, are considered the most dangerous. Fine particles can easily bypass filters in the nose and throat and penetrate deep into the lungs. Wood smoke from woodstoves and fireplaces is the major source of fine particulate matter in the wintertime in the Bay Area.

Clean HEET Program
Are you interested in helping clean up your neighborhood? The Air District's Clean HEET Program offers homeowners up to $10,500 to replace their wood or pellet burning fireplaces, stoves, or inserts with energy-efficient electric heat pumps. Learn more and sign up for updates at the Clean HEET website. 

Health Effects

Lung Irritation

This can lead to increased permeability, or the ability of liquids and gases to pass through to the lungs.

Lung Tissue Inflammation

As a result, chemicals can be released that can impact heart function.

Greater Severity of Chronic Lung Diseases

This can lead to the rapid loss of airway function.

Changes in Blood Chemistry

Clots can then occur that lead to heart attacks.

Increased Viral and Bacterial Pathogen Susceptibility

Vulnerable people who are unable to clear these infections can contract pneumonia.

Since the 1980s, many scientific studies have been published that correlate the exposure to wood smoke and particulate matter with serious public health effects, such as higher instances of asthma, decreased lung function in children, increased hospital admissions, and elevated mortality rates.

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