Assessing Outdoor Air Near Schools
St. Helen's Elementary School - Longview, WA
Results and Analysis of EPA’s monitoring
EPA selected this school for monitoring because it is located near a pulp and paper mill which is a source of air toxics emissions. Computer models were used to determine which air toxics may be present at elevated levels in the outdoor air near the school. These models showed that acetaldehyde, manganese, and nickel could be present in the air around the school and prompted EPA to test to see if the levels present may be of concern.
| Primary Findings | Levels of acetaldehyde, manganese, and nickel in the air at the school are below levels of health concern for short-term and long-term exposure. |
| Key Pollutants Monitored | Acetaldehyde. Exposure to high levels can cause irritation of the eyes, skin and upper respiratory tract. Manganese. Inhalation may affect the nervous system if people are exposed to high levels. Nickel. Inhalation may affect the respiratory system if people are exposed to high levels. |
| Next Steps | Because the acetaldehyde, manganese, and nickel levels are below levels of health concern, EPA will not extend air toxics monitoring at St. Helen's Elementary School. EPA remains concerned about nationwide emissions from sources of air toxics and continues to work to reduce those emissions across the country, through national rules and by providing information and suggestions to assist with air pollution reductions in local areas. The Southwest Clean Air Agency (SWCAA) and Washington State Department of Ecology's (Ecology) Industrial Section will continue to oversee industrial facilities in the area through their air permits and other programs. |
Summary of Study Approach and Findings
Approach:
- A monitor collected air samples from August 23, 2009 through November 15, 2009 at the St. Helen's Elementary School in Longview, Washington.
- We posted individual air sample results on this website throughout the monitoring period to keep your community informed during the monitoring period.
- During the monitoring period, we evaluated the monitored concentrations to see if there was a concern from short-term exposures (e.g., several weeks).
- When the monitoring was complete, we analyzed the results to see if there was a concern from long-term exposures (over a lifetime).
- Also, when the monitoring was complete, we evaluated all the air samples from the on-site monitor. We also evaluated information on wind speed and wind direction from a weather monitor at the school, along with historical weather information and information about nearby source(s) of acetaldehyde, manganese, and nickel emissions.
Findings:
- Our analysis found that levels of acetaldehyde, manganese, and nickel in the air at the school are below levels of health concern for long-term exposure.
- The concentrations of acetaldehyde, manganese, and nickel measured at the school are lower than those suggested by the information that first helped identify this school for monitoring.
- The process to identify schools for monitoring relied on emissions estimates and other information. Ambient air monitoring at the school allowed measurement of what was actually in the air.
- Information from the nearby pulp and paper mill source indicates that this facility was operating slightly above 2009 annual average levels (3,589 tons per day during the monitoring period versus 3,462 tons per day for all of 2009).
- Because the analysis shows monitored concentrations of acetaldehyde, manganese, and nickel levels to be below levels of health concern, EPA will not extend air toxics monitoring at St. Helen's Elementary School.
- Click here for additional information
How We Analyzed the Information We Collected at this School
The analysis considered whether the information collected at the school might raise concerns for the health of children or adults at the school. We looked at the following types of information:
- Measured acetaldehyde, manganese, and nickel concentrations and information on acetaldehyde, manganese, and nickel
- Measured wind direction and wind speed at the school
- Information about nearby sources of acetaldehyde, manganese, and nickel emissions
Analysis of Measured Acetaldehyde Concentrations:
1. Calculate the average: We calculated the average of the acetaldehyde measurements (shown by the black diamond in the graph below). We compared this average to the long-term comparison level (thick line on the graph below).
Result: The average The average acetaldehyde level for the samples collected was well below the long-term comparison level. The health concern is low.
2. Calculate a range: To account for varying air concentrations of acetaldehyde, we calculated a range around the average. We did this by estimating high and low values that the longer-term concentrations might reach using common statistical tools. We compared the highest point in the range (called the "upper bound") to the long-term comparison level.
Result: The high end of the range is lower than the comparison level. The health concern is low.
Analysis of Measured Manganese Concentrations:
1. Calculate the average: We calculated the average of the manganese measurements (shown by the black diamond in the graph below). We compared this average to the long-term comparison level (thick line on the graph below). The long-term comparison level represents the level of manganese in the air that is below levels associated with health concerns, even if someone breathed air containing manganese at that level all day, every day over their lifetime.
Result: The average manganese level for the samples collected was well below the long-term comparison level. The health concern is low.
2. Calculate a range: To account for varying air concentrations of manganese, we calculated a range around the average. We did this by estimating high and low values that the longer-term concentrations might reach using common statistical tools. We compared the highest point in the range (called the "upper bound") to the long-term comparison level.
Result: The high end of the range is lower than the comparison level. The health concern is low.
Analysis of Measured Nickel Concentrations:
1. Calculate the average: We calculated the average of the nickel measurements (shown by the black diamond in the graph below). We compared this average to the long-term comparison levels (values at the top of the graph below).
Result: The average nickel level for the samples collected was well below the long-term comparison levels. The health concern is low.
2. Calculate a range: To account for varying air concentrations of nickel, we calculated a range around the average. We did this by estimating high and low values that the longer-term concentrations might reach using common statistical tools. We compared the highest point in the range (called the "upper bound") to the long-term comparison levels.
Result: The high end of the range is lower than the comparison level. The health concern is low.
Analysis of Measured Wind Direction and Wind Speed at the School
We took measurements of wind direction and speed every day during the sample period. We took special note of the wind speed and direction on the days we took measurements of acetaldehyde, manganese, and nickel.
| What we looked at | What we found |
| We looked at whether the wind data taken on the days we took measurements of acetaldehyde, manganese, and nickel are similar or different from the wind patterns during the entire sampling period. | We found the wind patterns taken on the days we took measurements of acetaldehyde, manganese, and nickel to be somewhat similar to those observed during the entire sampling period. |
| We looked at whether the wind pattern during the sampling period is reflective of regional wind pattern over the long term. | Although we lack long-term wind data at the monitoring site, the wind pattern at the NWS station during the sampling period is generally similar to the historical long-term wind flow pattern at that same NWS station. This suggests that, on a regional scale, the 3-month sampling period may be representative of year-round wind patterns. |
Analysis of Information on Nearby Source of Acetaldehyde, Manganese, and Nickel Emissions
| What we looked at | What we found |
| Whether we could determine if mobile source activity was typical during the sampling period | Information from the nearby pulp and paper mill source indicates that this facility was operating slightly above 2009 annual average levels (3,589 tons per day during the monitoring period versus 3,462 tons per day for all of 2009). |
| The concentrations of acetaldehyde, manganese, and nickel measured at the school are lower than those suggested by the information that helped identify this school for monitoring. | |
| The nearby source of acetaldehyde, manganese, and nickel has a Title V operating air permits issued by Ecology that includes operating requirements. |
Additional Information
Technical Report for School: Assessing Outdoor Air Near Schools: St. Helen's Elementary School (Longview, WA) (PDF) (35pp, 234). The technical report is geared toward risk assessors, risk managers, and other regulatory agencies.
Background on School Monitoring Effort