146 - Spatial Associations of Particulate Matter (PM2.5) and Childhood Cancer in Massachusetts

Publication Number: 2140.146

Marissa Hauptman, Boston Children's Hospital, Boston, MA, United States; Diane Story, Boston Children's Hospital, Boston, MA, United States; Evelina Ceca, Dana-Farber Cancer Institute, Boston, MA, United States; Alan D. Woolf, Boston Children's Hospital, Boston, MA, United States

Background: While environmental exposures including traffic-related air pollution have been associated with greater risk of childhood cancer, clinicians often lack knowledge of their patients' environmental risk factors.

Objective: The Spatial Patterns and Risk of Childhood Cancer (SPARCC) study aims to identify spatial patterns of pediatric cancer and associated environmental risk factors across Massachusetts to inform clinical care. This analysis focuses on associations with particulate matter 2.5 exposure (PM2.5).

Design/Methods: This analysis included Massachusetts residents diagnosed with cancer at a Massachusetts pediatric cancer center. The mean yearly PM2.5 from the EPA's Downscaler model, 2001-2019, was linked to patient addresses and census-tract Childhood Opportunity Index (COI) 3.0 scores at the year of diagnosis. The global Moran's I statistic was calculated to identify spatial clustering of cases. A negative binomial model with a population offset was calculated to investigate an association between PM2.5 and census-tract cancer case rate. Logistic regressions controlling for age and census-tract level SES according to the COI 3.0 were calculated to investigate the odds of metastases and mortality by PM2.5 exposure.

Results: 2,365 patients had full address information, were Massachusetts residents, and were diagnosed between 2001 and 2019. There was significant evidence of spatial clustering of cancer rates (Moran's I 0.128, p-value: 0.001 for 999 permutations). When compared to the 1st quartile of PM2.5 exposure, census tracts in the 4th quartile had a 40% greater cancer rate, controlling for SES as measured by the COI (p <.001). Additionally, when controlling for SES and age at last contact, patients in the 3rd quartile of PM2.5 exposure had 67% greater odds of mortality compared to the 1st quartile of PM2.5.

Conclusion(s): There is evidence for significant spatial clustering of pediatric cancer cases in Massachusetts, and for an association between the fourth quartile of PM2.5 exposure and census-tract level cancer rate. Additionally, there was evidence for an association between the third quartile of PM2.5 exposure and patient mortality. Geomarkers derived from the electronic medical record can inform both clinicians and families of environmental risks, and help to identify, advocate for and educate about environmental exposures, from prior to diagnosis through survivorship.

Pediatric cancer rate by quintiles of COI, social and economic domain
Cancer case rate per 1000 population under 21 years old by census tract level SES, as measured by the Social and Economic Domain of the Childhood Opportunity Index.

Pediatric cancer rate by quintiles of PM2.5
Cancer case rate per 1000 population under 21 years old by census tract level PM2.5. PM2.5 indicates the mean yearly level in ug/L from the EPA Downscaler model, averaged from 2001-2019.