Associations of Racial and Ethnic Composition of School Districts with Wildfire Smoke Exposure and Reduced In-Person Learning Among Schoolchildren During the Pandemic in the United States

Introduction. The White House has called for an "all-hands-on-deck" response to address chronic absenteeism and disrupted learning among K-12 students that spiked during the COVID-19 pandemic due to school closures and shifts to remote learning in the United States. Such learning disruptions are linked to test score declines with lifelong implications for earnings and well-being. This study aimed to identify higher-risk student populations that might benefit from interventions to reduce such disruptions and related inequities by estimating the linkages between the racial and ethnic composition of U.S. K-12 school districts as predictors of average wildfire smoke levels and year-over-year declines in in-person student visits to schools during the pandemic. Methods. Using multivariable logistic regression, 5-year (2012-2016) mean percentages of non-White students grouped into quartiles were investigated as predictors of school district-level outcomes consisting of: 1) 5-year (2012-2016) mean levels of wildfire smoke fine particulate matter 2.5 μm or smaller in diameter (PM2.5) above 35 μg/m3 (EPA health-based standard) during school days for grade 3-8 students from August 15 to June 15 of the following year; and 2) being above the median for the mean decline in in-person student attendance (vs. the same month in 2019), from September 2020 to May 2021 and September 2021 to May 2022. Results. Across 11,190 (82.4% of all) U.S. school districts, the highest (vs. lowest) quartile for the percentage of non-White students predicted a nearly 3-fold higher odds (adjusted odds ratio, AOR=2.82; 95% CI=2.14-3.72; P<.001) for high wildfire smoke exposure and a 9-fold higher odds (AOR=9.12; 95% CI=7.15-11.63; P<.001) for substantially reduced in-person learning levels. Successively higher odds were observed in higher quartiles (P for trend <.001). Similar patterns were seen when high (vs. low) percentages of Asian-, Black-, and Hispanic-American students were modeled simultaneously. Conclusions: U.S. school districts with higher percentages of non-White students showed a convergence of elevated odds of wildfire smoke exposure and distance learning consistent with dose-response relationships. These concomitant risks could be mitigated by school-based air filtration interventions that reduce wildfire smoke PM2.5 and transmission of airborne particulates carrying the coronavirus. One potential cost-effective intervention to address these joint risks would be the placement of Corsi-Rosenthal boxes (DIY inexpensive portable air filtration devices shown to effectively reduce PM2.5 concentrations) in school classrooms and other school indoor areas. Supplying Corsi-Rosenthal boxes to school districts could markedly reduce learning disruptions and wildfire smoke and COVID-19 health impacts and their related inequities at a cost of less than $1 billion annually, 0.5% of the $190 billion in federal relief available to school districts to address pandemic-related needs including learning loss. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement This study did not receive any funding. ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes All data produced in the present study are available upon reasonable request to the author.