Reviewing key sources and common pollutants
By Zarin Hussain, MPH (c) and Derek G. Shendell, D. Env., MPH
Why is this topic important?
There are many environmental health and safety issues facing New Jersey’s K-12 schools every day. One of them is mostly beyond the jurisdiction of the school district and individual school and is driven by both natural and human sources.
What is it? It’s outdoor or ambient air quality surrounding a campus and its buildings occupied daily by public school staff and students. These individuals may be managing asthma and other chronic health conditions, making them more susceptible to exposure and more vulnerable to health risks.
In this article, we briefly summarize the major pollutants of concern and associated adverse health outcomes. We note that some pollutants do have indoor combustion sources, but they tend to be present less often in school classrooms compared to homes and many worksites.
Particulate matter
There are two size fractions or aerodynamic diameters used by government agencies and researchers to describe particulate matter or particles (PM): respirable or coarse, PM10, and fine, PM2.5.
In general, excluding natural sources of PM (e.g., pollen from grass, flowers, trees and weeds), PM10 is typically more associated with dust on roads and surfaces both indoors and outdoors, and PM2.5 is typically more associated with combustion of fossil fuels like oil, natural gas, diesel, coal and wood.
Factors such as idling and traffic contribute to higher levels of exposure among K-12 students, and frequently cause adverse health impacts on students. Since the bodies of these students are not fully developed, the impacts of exposure to particulate matter are more serious in contrast to staff. Even though serious impacts are experienced by children, long-term exposure can trigger adverse health outcomes for staff.
According to one study, children who were located farther from school in an area with less traffic experienced higher levels of exposure to particulate matter while students who walked to school in an area with high levels of traffic had lower exposures. This was due in part to the fact buses—mostly operated on diesel fuel known to have higher pollutant emissions including PM2.5—are commonly used to transport students living farther away.
There is a correlation between exposure to PM10 or less and negative effects on test scores and reasoning. There is a positive correlation between PM2.5 exposure from traffic and negative health outcomes among students of color and those who are eligible for subsidized meals. There is a correlation between PM2.5 exposure caused by traffic and visits to the emergency room due to issues with asthma.
Nitrogen oxides
Nitrogen oxides, especially nitrogen dioxide or NO2, are recognized as one of the most serious air pollutants among K-12 schools. Exposure to nitrogen oxides, especially nitrogen dioxide, not only triggers adverse health impacts among students, but is also one of the most crucial particles involved in the chemical reaction necessary to form other pollutants such as ozone. This triggers more adverse health impacts among students since their bodies are not fully developed.
Students are frequently exposed to NO2 from traffic located near schools, particularly among students of color and those of low income. Exposure to nitrogen compounds among students with asthma could potentially increase the risk of inhibition of proper airflow.
According to a review, there is a correlation between exposure to NO2 and negative impacts on working memory. High exposure to NO2 potentially increases the chance of lung disease among students. Exposure to NO2 leads to this compound reacting with the immune system and increases the chance of the development of respiratory tract infections. Notably the chemical reaction between nitrogen compounds, sunlight and volatile organic compounds leads to the formation of ground level ozone.
Ozone
Sources of direct emissions of ozone indoors include equipment that releases the gas such as photocopiers, air cleaners and printers. Factors such as a building’s age, window openings, air conditioning, carpeting and window fans are correlated to the level of ozone indoors. Exposure, even within the limits of current federal and state ambient or outdoor air quality standards, still heavily affect rates of absences from school among all grade levels and schools of various socioeconomic backgrounds. All this while the current limits may be considered only initial guidelines for indoor air quality.
Notably, even higher ozone and particulate rate ratios were found among those in elementary school than those in the middle and high school levels. This is because younger children’s lungs are still not fully developed and are therefore more vulnerable to ozone and PM2.5. This disparity held even when the elementary school had lower levels of exposure than the higher grades.
According to a study, there was a correlation between exposure to pollutants such as PM2.5 and absences. There is also a correlation between exposure to each of these contaminants and the number of absences from school.
Other gases
Traffic directly and indirectly leads to exposure to air pollutants—both outdoors and indoors via open windows and doors or poorly functioning mechanical ventilation systems with filtration—including such particulate matter as PM2.5 and PM10, nitrogen oxides including NO2, carbon monoxide or CO, sulfur dioxide or SO2, and selected volatile organic compounds known or suspected as toxic.
Notably, SO2 leads to respiratory problems among those who are healthy and patients with pulmonary disease. Exposure to SO2 (based on experimental results) changes the airway and increases the resistance of the airway.
Notably, there is a correlation between both acute and chronic exposure to carbon monoxide and negative cardiopulmonary outcomes.
What can local associations do?
It is critical to prevent exposure to these ambient air pollutants. One way this could be accomplished is by reducing idling outside of schools. In New Jersey, this is the law, and cars, trucks and buses are restricted to no more than three minutes of idling year-round.
In addition, we recommend:
1. Provide adequate ventilation, with sufficient particulate matter filtration.
2. To reduce exposure, decrease the use of equipment (e.g., printers) and products such as chemicals used for cleaning because they release ozone and substances that react with ozone.
Resources
International Journal of Environmental Research and Public Health
“School Locations and Traffic Emissions—Environmental (In)Justice Findings Using a New Screening Method”
By Philine Gaffron and Deb Niemeier
bit.ly/4crcKJC
“The Effects of Traffic Air Pollution In and Around Schools on Executive Function and Academic Performance In Children: A Rapid Review”
By Nicola Gartland, Halah E. Aljofi, Kimberly Dienes, Luke Aaron Munford, Anna L. Theakston and Martie van Tongeren
bit.ly/4a6pie3
Journal of Urban Affairs
“Impact of School Location on Children’s Air Pollution Exposure”
By Mary K. Wolfe, Noreen C. McDonald, Saravanan Arunachalam, Richard Baldauf and Alejandro Valencia
bit.ly/3PqbFaL
New Jersey Department of Environmental Protection
Compliance and Enforcement
Previous ACEAcademy Training Presentations
“Idling Regulations and Idling Enforcement”
bit.ly/3vhr6vl
U.S. Environmental Protection Agency
“Sources of Indoor Particulate Matter”
bit.ly/4apx0th