MINNEAPOLIS/ST. PAUL (2/21/2024) — In a new study led by the University of Minnesota’s Masonic Cancer Center and the U of M Medical School, researchers found that exposure to air pollution and vegetation may impact childhood cancer development. The study was published in the Journal of the National Cancer Institute.

The population-based study, led by U of M Medical School Assistant Professor Lindsay Williams, MPH, PhD, in collaboration with U of M Institute for Health Informatics Assistant Professor David Haynes, PhD, examined over 6,000 children with cancer and 109,000 children without cancer in Texas. The study found that from 1995-2011 increasing exposure to fine particulate matter (PM2.5) during the birth year increased the risk of developing any childhood cancer and specifically lymphoid leukemia, lymphoma, ependymoma, retinoblastoma and thyroid carcinoma. 

“As a childhood cancer epidemiologist, I am always concerned with identifying factors that increase risk of cancer development in kids,” said Dr. Williams. “There is growing evidence that air pollution during pregnancy and fetal development increases the risk of developing some diseases in children, including cancer.” Williams noted that identifying particular exposures that could decrease the risk for developing childhood cancer has proven challenging in the past as there are very few of these that have been identified to date. 

To that end, her team decided to examine environmental exposures that might reduce the risk of developing childhood cancers. To do so, they examined the association between residential greenness — or vegetation density around the home — and childhood cancer risk, as plants can remove up to 20% of PM2.5 from the air. Findings indicate that increasing exposure to residential greenness reduced the risk of developing ependymoma and medulloblastoma — the two most commonly diagnosed malignant brain tumors in children. These associations for PM2.5 and greenness also remained after accounting for both co-exposures in the team’s statistical models, suggesting that these exposures independently modulate risk for some childhood cancers. 

Williams and team stress that these exposures to air pollution and, conversely, to greenness are potentially modifiable risk factors that could be targeted as risk reduction and and prevention strategies through policy measures and/or through changes in environment, such as planting more trees and vegetation. 

Future work is underway to examine more specific timing of exposures during pregnancy and other air pollutants to better understand how the composition of air pollution, which is a complex chemical mixture, impacts childhood cancer development. 


About the Masonic Cancer Center, University of Minnesota

The Masonic Cancer Center, University of Minnesota, is the Twin Cities’ only Comprehensive Cancer Center, designated ‘Outstanding’ by the National Cancer Institute. As Minnesota’s Cancer Center, we have served the entire state for more than 30 years. Our researchers, educators, and care providers work to discover the causes, prevention, detection, and treatment of cancer and cancer-related diseases as well as provide whole-of-life care and resources for survivorship. Learn more at cancer.umn.edu.

About the University of Minnesota Medical School

The University of Minnesota Medical School is at the forefront of learning and discovery, transforming medical care and educating the next generation of physicians. Our graduates and faculty produce high-impact biomedical research and advance the practice of medicine. We acknowledge that the U of M Medical School is located on traditional, ancestral and contemporary lands of the Dakota and the Ojibwe, and scores of other Indigenous people, and we affirm our commitment to tribal communities and their sovereignty as we seek to improve and strengthen our relations with tribal nations. For more information about the U of M Medical School, please visit med.umn.edu.