Village Green Project: What’s in our Air?

By Ronald Williams

What’s in our air? It’s made up of 78 percent nitrogen, 21 percent oxygen, and one percent other gases such as carbon dioxide.  An even smaller contribution comes from gaseous air pollutants such as ozone or carbon monoxide.  In addition to the gases, air contains tiny particles from both natural and man-made processes.

In the Village Green Project, my EPA colleagues and I are developing a community-based system that repeatedly measures select gases and particles so residents can monitor local air quality and know what’s in their air.

Here are three important components:

Knowing daily changes in ozone concentrations is very important, especially to those with respiratory illnesses such as asthma.  Ozone is generally highest on sunny summer days, when sunlight fuels atmospheric chemistry and generates ozone from a mixture of emissions.   The Village Green monitor will report ozone many times during the course of the day, showing how ozone levels go up and down based upon air pollution emissions and sunlight.

Particulate Matter

Particulate matter. For a larger version, go to:

All of us are exposed to particulate matter from a wide variety of local and distant sources.  After being produced, particles can transport hundreds of miles.  We encounter it in our homes, in our cars, in our work places, and out in our yards.  Understanding how it changes in the environment on a day-by-day and even hour-by-hour basis will help local citizens be better informed about this pollutant, which has been associated with a wide variety of human health effects.

Black Carbon
There’s an old saying that ‘everyone complains about the weather, but no one ever does anything about it.’ Now here’s our chance to learn about a pollutant that may affect our climate and is also important for health. Scientists now know that combustion products, such as black carbon, have the potential to influence climate change.  Black carbon is also a good indicator of emissions from fuel-burning, including from vehicles, forest fires, and smoking.  By monitoring black carbon levels in local air, the Village Green Project will help increase our understanding of links between local pollution sources and their impact on black carbon.

Even before the monitor is up and running, we’ve received regular inquiries about the Village Green Project from community groups, environmental scientists and those involved in air quality research.  Cleary, we’ve struck a nerve with citizens, and the desire of local communities to know what’s in their air and gain information about local air quality is ever-growing!

We expect the Village Green monitor will be operating this summer.  Stay tuned to this blog for more (and for our future web site) as we move forward.

About the Author: Ron Williams is an exposure science researcher who is studying how people are exposed to air pollutants and methods to measure personal exposure.

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