Ewing sarcoma is a rare and aggressive cancer that primarily affects the bones and soft tissues of children and adolescents. The disease is characterized by a chromosomal translocation involving the EWS-FLI1 fusion gene, yet experimental evidence suggests that this genetic alteration alone may not be sufficient to cause cancer. Additional mutations or cellular changes are likely required, and environmental exposures, including those occurring before birth, have been proposed as one possible mechanism contributing to these additional alterations.
Despite these biological clues, little is known about environmental causes of Ewing sarcoma. The cancer remains underrepresented in environmental epidemiology research, and previous studies investigating potential environmental risk factors have produced mixed findings. Oil and gas development (OGD) has emerged as one environmental exposure of interest, especially as millions of people in the United States live near active, plugged, or abandoned oil and gas wells. OGD activities involve the use and release of a variety of potentially carcinogenic compounds and have been linked to increased risk of childhood leukemia. However, the influence of these exposures on risk of other pediatric cancers remains largely unexplored.
To address this gap, CLIC researchers conducted a large population-based case–control study using data from the California Linkage Study of Early-Onset Cancers. The study included 558 children diagnosed with Ewing sarcoma between 1988 and 2015 and 27,800 cancer-free controls matched by birth year. Using maternal residential address at birth, the investigators examined whether prenatal exposure to active or abandoned oil and gas wells may be associated with risk of childhood Ewing sarcoma. Exposures were assessed within distances of up to 10 km during the period from three months before conception through birth.
Overall, the study did not find evidence that living near active oil and gas wells during pregnancy was associated with an increased risk of Ewing sarcoma in children. However, researchers observed a suggestive elevation in risk among children whose mothers lived near abandoned wells during pregnancy. The analysis also revealed notable exposure disparities: hispanic children were substantially more likely than non-Hispanic children to live near both active and abandoned oil and gas wells. In stratified analyses, the elevated risk associated with abandoned wells appeared primarily among Hispanic children.
Because the etiology of Ewing sarcoma remains poorly understood, unmeasured environmental or genetic factors could also contribute to the observed patterns. The findings should therefore be interpreted cautiously. Nonetheless, the study provides one of the largest investigations of environmental risk factors for this cancer to date. It also expands research on oil and gas development beyond leukemia to consider other rare childhood malignancies.The results suggest that prenatal exposure to abandoned oil and gas wells may warrant further investigation as a potential environmental risk factor for Ewing sarcoma. Future studies in other regions with different patterns of oil and gas activity will be important for confirming these findings and better understanding how early-life environmental exposures may contribute to childhood cancer risk.
Citation:
Article Title: Residential proximity to active and abandoned oil and gas development and risk of childhood Ewing sarcoma in California
Authors: Cassandra J. Clark, Nicholaus Johnson, Rong Wang, Eric C. Stewart, Logan G. Spector, Joseph L. Wiemels, Catherine Metayer, Nicole C. Deziel, Xiaomei Ma.
Published In: Environ Health. 2026 Jan 14;25(1):12. doi: 10.1186/s12940-025-01259-3.