This page last reviewed October 21, 2010

Air Monitoring Results

These data represent only a portion of the data that have been collected as part of this study. Although the air quality monitoring in Fresno ended in August 2003, not all of the data have been processed and reviewed. Therefore, no conclusions about the overall meaning of the data should be made at this time.

Monitoring details

The monitoring of ambient air quality at Fremont Elementary School began in June 2002 and ended in August 2003. A table of air pollutants monitored is provided here. Fremont Elementary School, located in Fresno, is one of six sites chosen for Children's Environmental Health Protection monitoring. It is located in a residential neighborhood approximately 1/2 mile east of highway 99. Fresno was chosen due to its location nearby traffic (where pollution from cars and trucks can be significant) and the high number of children living in the community. The Fresno school system is the 4th largest in California, with over 80,000 students in 61 elementary schools, 16 middle schools, and 9 comprehensive high schools. Students in the Fresno school system speak 101 different languages.

While the main source of emissions nearby Fremont Elementary School are mobile sources such as cars and trucks, other sources include train yards, distribution warehouses, and metal fabrication along an avenue parallel to highway 99.

Criteria Pollutants

Some air pollutants have health-based standards established; a standard is a level above which a pollutant is known to cause adverse health effects in humans. Among the so-called criteria pollutants, ozone, carbon monoxide, and oxides of nitrogen are monitored routinely at several nearby sites, including: Clovis-N. Villa Avenue, Fresno-First Street, Fresno-Drummond Street, Fresno-Sierra Skypark #2, and Parlier. Particulate matter and fine particulate matter are monitored routinely at the following nearby sites: Clovis-N. Villa Avenue, Fresno-First Street, and Fresno-Drummond Street. Information on these so-called criteria pollutants can be obtained below:

High Risk Toxic Air Pollutants

The Air Resources Board has identified the top 10 high risk toxic air pollutants and nine of them were measured in Fresno at Fremont Elementary School. The top 10 high risk toxic air pollutants have potential health risks and cancer risks. Ambient levels of these toxic air pollutants are routinely monitored at approximately twenty sites in the California air toxics monitoring network. Closest to Fremont Elementary in the same county is Fresno-First Street where data for the last 4 years are available for comparison. Diesel particulate matter is a significant contributor to the potential cancer risk from air toxics in California, but diesel particulate matter was not measured at Fremont Elementary School because a method for directly measuring this pollutant is still being developed. However, the potential cancer risk is estimated for diesel particulate matter for the entire San Joaquin Valley air basin. As shown in a graph illustrating the cancer risk due to individual pollutants, diesel particulate matter is the highest contributor to risk from air toxic pollutants. The next highest are benzene and 1,3-butadiene. Information on these nine high risk toxic air pollutants can be obtained below:

Metals of interest

Some metals were of particular interest in this study. Information on these metals are below:

Diesel Particulate Matter and Elemental Carbon

While diesel particulate matter contributes the most to overall risk from toxic air contaminants, it has proved very elusive to measure. We are exploring the options to estimate the impact of diesel particulate matter on public health in the community, including using elemental carbon as an estimator. However, there are technical difficulties using elemental carbon to estimate diesel particulate matter. First, other sources of elemental carbon besides diesel particulate matter became more significant as emissions from the diesel fleet decreased as a result of improved diesel technologies. Second, there are two elemental carbon analysis methods that have evolved, which give significantly different results when measuring the same particles in the air. In this study, the Air Resources Board uses one elemental carbon analysis method. Information on elemental carbon are presented below:

PAHs and Dioxins

Polycyclic aromatic hydrocarbons (PAHs) and dioxins have been identified as toxic air pollutants that may impact infants and children more than the rest of the population. The PAHs are monitored in this study as one group . The link below provides information on current activities on dioxins monitoring. There is no dioxin monitoring at Fremont Elementary School. Information on PAHs and other compounds can be obtained below:

  • PAHs
  • Dioxins (not available at Fremont Elementary School)

All approved data

For all available approved data in Microsoft Excel format: