The environmental determinants of pediatric embryonal tumors remain unclear. Because of the growing concern over the impact of exposures to traffic-related air pollution on pediatric cancer, we conducted a population-based study evaluating the impact of maternal residential proximity to major roadways on the risk of pediatric embryonal tumors in offspring. We identified children diagnosed with neuroblastoma, Wilms tumor, retinoblastoma, or hepatoblastoma at <5 years of age from the Texas Cancer Registry and selected unaffected controls from birth certificates. Two residential proximity measures were used: (1) distance to the nearest major roadway, and (2) within 500 m of a major roadway. Logistic regression was used to estimate the adjusted odds ratio (aOR) and 95% confidence interval (CI) for each proximity measure on pediatric embryonal tumors. The odds of an embryonal tumor were increased in children born to mothers living within 500 m of a major roadway (aOR = 1.24, 95% CI: 1.00, 1.54). This was consistent for most tumor subtypes, with the strongest associations observed for unilateral retinoblastoma (aOR = 2.57, 95% CI: 1.28, 5.15, for every kilometer closer the mother lived to the nearest major roadway). These findings contribute to the growing evidence that traffic-related air pollution may increase risk for certain pediatric tumors.
