Assessing Outdoor Air Near Schools
Harriet Tubman Middle School - Portland, OR
- Understanding the Monitoring Data
- Initial Sample Results
- Initial Analysis
- Additional Sample Results
- Final Analysis
EPA selected this school for monitoring because it is in a community that is impacted by several major highways. Based on emissions from nearby sources, EPA identified key pollutants to measure in the air near this school. The initial monitoring conducted starting in August through November 2009 indicated a need to better understand a source of cadmium in the community and its potential impact on the community. EPA conducted additional monitoring at this school from May through July 2011. We reported concentrations of the key pollutant, cadmium, in the table below. While the key pollutant is cadmium, other metals were also measured and that data is available (PDF) (4pp, 54k).
About the Data
The table below shows the levels of the key pollutant in air samples collected at the monitoring site beginning in May 2011. The table also includes individual “sample screening levels” for cadmium. EPA developed screening levels to help the Agency and the community get an early sense of what the data were showing. The sample screening level is a level of pollution in the air that is below what we expect to cause health problems from short-term exposures – all day, every day over a period ranging up to at least a couple of weeks (longer, for some pollutants). Screening levels are used only as guidelines for this project.
About The Table
Compare the sample results to the short-term screening level at the top of the table. Numbers at or below that level indicate the pollutant is not likely to pose immediate health concerns.
To use the screening level, compare it to each sample result:
- a sample result at or below the sample screening level is not a concern for risk of health problems from short-term exposures.
- a sample result above the screening level does not mean that there is a risk to children and adults at the school. It is a signal for EPA to further evaluate those and subsequent results for that pollutant.
After monitoring was completed, EPA analyzed the potential for health concerns from long-term exposure. The analysis may be found under the Final Analysis tab. Monitoring results are in the table below.
| Key Pollutants | Cadmium (Nanograms/cubic meter) |
|---|---|
| Sample Screening Level | 30 |
| 05/27/11 | 0.88 |
| 05/28/11 | 0.10 |
| 05/29/11 | 0.19 |
| 05/30/11 | 11.6 |
| 05/31/11 | 1.44 |
| 06/01/11 | 1.27 |
| 06/02/11 | 5.14 |
| 06/03/11 | 12.6 |
| 06/04/11 | 0.08 |
| 06/05/11 | 0.11 |
| 06/06/11 | -- |
| 06/07/11 | 0.65 |
| 06/08/11 | 0.16 |
| 06/09/11 | 0.04 |
| 06/10/11 | 0.05 |
| 06/11/11 | 0.04 |
| 06/12/11 | 0.29 |
| 06/13/11 | 0.33 |
| 06/14/11 | 0.07 |
| 06/15/11 | 0.04 |
| 06/16/11 | 4.88 |
| 06/17/11 | 0.06 |
| 06/18/11 | 0.19 |
| 06/19/11 | 0.05 |
| 06/20/11 | 0.20 |
| 06/21/11 | 0.05 |
| 06/22/11 | 0.04 |
| 06/23/11 | 0.05 |
| 06/24/11 | 0.09 |
| 06/25/11 | 0.02 |
| 06/26/11 | 0.09 |
| 06/27/11 | 2.43 |
| 06/29/11 | 1.30 |
| 06/30/11 | 0.56 |
| 07/01/11 | 0.09 |
| 07/06/11 | 0.05 |
| 07/07/11 | 0.05 |
| 07/08/11 | 0.05 |
| 07/09/11 | 0.04 |
| 07/10/11 | 0.07 |
| 07/11/11 | 1.21 |
| 07/12/11 | 2.86 |
| 07/13/11 | 4.51 |
| 07/14/11 | 0.97 |
| 07/15/11 | 1.75 |
| 07/16/11 | 0.05 |
| 07/17/11 | 0.32 |
| 07/18/11 | -- |
–– = Sample not taken or invalid
Also monitored (PDF) (4pp, 54k)