Criteria Pollutants

OEHHA is responsible for the periodic review and recommendations for health-based ambient air quality standards (AAQS) for common (or so-called “criteria”) air pollutants such as particulate matter, ozone, nitrogen dioxide and carbon monoxide*.   It carries out these mandated responsibilities under the Health and Safety Code (Sections 425, 39606) and the Children’s Environmental Health Protection Act (Senate Bill 25, Escutia, 1999).  The former mandates requires the periodic review by OEHHA of the health effects of pollutants for the development of health-based recommendations for the AAQS and for OEHHA to inform the California Air Resources Board of new pollutants, averaging times and susceptible populations that could necessitate changes in the AAQS.  The latter law requires OEHHA to develop pollutant standards that may not be protecting the health of infants and children with an adequate margin of safety.  The recommendations are made after careful peer review by the independent Air Quality Advisory Committee and after several public hearings.

OEHHA also conducts its own epidemiological investigations of the health effects of criteria pollutants commonly found in the urban environment including particulate matter (PM10 and PM2.5), ozone, nitrogen dioxide and carbon monoxide, to enhance the quality of our recommendations.

Criteria Air Pollutants

  • Ozone
  • Particulate Matter
  • Carbon Monoxide
  • Nitrogen Oxides
  • Sulfur Dioxide
  • Lead

*Visibility Reducing Particles, Sulfates, Hydrogen Sulfide, and Vinyl Chloride are not considered criteria pollutants, but have California Ambient Air Quality Standards

Additional background about these air pollutants, the development of ambient standards, existing state monitoring and the status of attainment of these standards can be found on the Air Resources Board web site.

Criteria Pollutant News

Jun 18, 2020: Adverse Pregnancy Outcomes Linked to Climate Change
Higher rates of preterm birth, low birth weight and stillbirth are linked to increased heat, ozone and fine particulate matter, according to a meta-analysis released today and co-authored by...
Aug 31, 2004: Review of the Ambient Air Quality Standard for Ozone
The objective of this August 2004 draft chapter is to quantify the potential reductions in adverse health effects from reduced exposures to ozone from attaining the ozone standards recommended in the...