A University of Utah study has found that even low levels of ozone and fine particulate matter exposure are associated with increased school absences in the Salt Lake City School District, highlighting a growing concern for student health and economic stability. The findings arrive as state health officials continue to promote specific recess guidelines designed to protect children from respiratory risks during periods of poor air quality.
Impact of Low-Level Pollution
The research, published by University of Utah researchers, analyzed PM2.5 and ozone concentrations at 36 different schools from July 2015 to June 2018. Using a dense network of regulatory and mobile sensors—including sensors mounted on electric Utah Transit Authority light-rail trains—the study demonstrated that pollution impacts vary significantly between individual schools, a distinction that can be lost when using averaged regional pollution levels.
According to the study, even when pollutant levels remained below the Environmental Protection Agency's Air Quality Index breakpoints for 'good' air quality, an association with increased absences persisted. Specifically, the researchers estimated a rate ratio of 1.04 absences per μg m−3 increase in PM2.5 and 1.01 per ppb increase for ozone. This suggests that even concentrations previously considered safe can contribute to student absenteeism.
Economic and Social Costs
Beyond health implications, the study quantified the economic consequences of air pollution-related absences. The researchers estimated that reducing pollution by 50% could save the school district $426,000 annually. These savings would encompass lost school revenue, productivity, and the economic burden placed on families.
The research also highlighted a significant environmental justice component, noting that pollution reduction benefits would be greatest in schools located in socioeconomably disadvantaged areas. The study found that heterogeneity in exposure disproportionately affects these schools, pointing to a critical need for fine-resolution exposure estimation to protect vulnerable student populations.
State Recess Recommendations
To mitigate these health risks, the Utah Asthma Program provides specific recommendations for elementary school students through its Utah Recess Guidance. The guidance is designed to advise schools on when students should remain indoors during recess based on current air quality levels, specifically focusing on PM2.5, which is the primary pollutant of concern during Utah's winter months.
The program aligns its recommendations with the Utah Department of Environmental Quality. While EPA recommendations are often written for adults based on 24-hour exposure averages, the Utah Recess Guidance is specifically tailored to account for the shorter, 20-to-30-minute outdoor recess exposures typical of children. The guidance also considers students with pre-existing respiratory conditions or those currently exhibiting respiratory symptoms, who may be more sensitive to poor air quality than their peers.
Development of Guidance
The current framework for these recommendations was developed following the third Air Quality and Health Summit held in June 2016. The summit involved 53 participants from 27 different stakeholder organizations, including health scientists, healthcare professionals, school representatives, and parent groups. During this meeting, attendees reviewed topics ranging from EPA Air Quality Index and Flag Program recommendations to physical activity research and school logistics.
Following discussions at the summit, participants determined that the guidance needed updating to better align with state environmental recommendations and to meet the specific needs of Utah communities.
Feedback From Schools
Educators and healthcare professionals in various districts have reported that the guidance is a vital tool for daily decision-making. Diane Broadhead, a Registered Nurse with the Davis School District, noted that some schools refer to the guidance daily and monitor particulate counts each day when air quality is in question.
Other school officials expressed how the alerts assist in maintaining student safety. BJ Weller, a Licensed Clinical Social Worker at Canyon View Elementary, stated that the guidance has been critical in helping staff know how to keep students healthy and safe. Similarly, Pam Mertz of Summit Christian Academy noted that while they try to keep students outdoors as much as possible, it is important to know when outdoor recess is not a healthy choice.
Ease of Access
The integration of accessible digital resources has also been cited as a benefit by school administrators. Trudy Messick of Renaissance Academy noted that the guidance makes it easy to determine if air quality is safe for play because educators can simply click a link in an email to view local air quality without having to conduct extensive manual searches.
As research continues to highlight the granular impacts of pollutants like ozone and PM2.5 on school attendance and district-wide economics, these localized guidance tools remain a primary resource for Utah's educational institutions.
