Data from Ambient Fine Particulate Matter, Residential Greenness, and Childhood Cancer Risk by Trimester of Exposure in Minnesota 2000 to 2014: A Case–Control Study

<div>AbstractBackground:<p>Outdoor air pollution is a suspected risk factor for childhood cancer, and there is some evidence that greenness may reduce cancer risk. We examined relationships between prenatal exposure to ambient fine particle air pollution [particulate matter <2.5 µg/m<sup>3</sup> (PM<sub>2.5</sub>)], greenness, and childhood cancer risk in Minnesota.</p>Methods:<p>Cases included individuals born in the state of Minnesota and reported to the Minnesota Cancer Reporting System between 2000 and 2014 (<i>n</i> = 1272, ages 0–14 years at diagnosis) and birth year–matched cancer-free controls (<i>n</i> = 5245). We used Network Common Data Form to estimate monthly PM<sub>2.5</sub> exposure and the normalized difference vegetation index for census tract–level greenness. We estimated ORs and 95% confidence intervals (95% CI) between high PM<sub>2.5</sub> (≥12 µg/m<sup>3</sup>) and normalized difference vegetation index (≥0.3) exposure and each childhood cancer per trimester (T1, T2, and T3) and full pregnancy using adjusted logistic regression.</p>Results:<p>High PM<sub>2.5</sub> exposure was associated with increased odds of Burkitt lymphoma [OR<sub>T1</sub>: 1.93 (1.13–3.30)], lymphoreticular neoplasms [OR<sub>T1</sub>: 1.43 (1.01–2.01)], Hodgkin lymphoma [OR<sub>T2</sub>: 2.60 (1.52–4.45)], lymphoid leukemias [OR<sub>T3</sub>: 1.17 (1.01–1.37)], B-cell leukemia [OR<sub>T3</sub>: 1.20 (1.02–1.41)], and intracranial and intraspinal embryonal neoplasms [OR<sub>T3</sub>: 1.90 (1.07–3.37)]. High residential greenness during early life was associated with reduced risk of malignant epithelial neoplasms and melanomas [OR<sub>T1</sub>: 0.34 (0.13–0.91)]. Unexpectedly, greenness was also associated with increased risk of renal tumors [OR<sub>T2</sub>: 1.52 (1.11–2.08); full pregnancy OR: 1.30 (0.98–1.72)] and neuroblastoma [OR<sub>T3</sub>: 1.44 (1.03–2.03)].</p>Conclusions:<p>We observed elevated risk associated with PM<sub>2.5</sub> exposure throughout pregnancy for multiple individual cancers, namely leukemias, lymphomas, and central nervous system tumors.</p>Impact:<p>These findings demonstrate the complex relationship between PM<sub>2.5</sub> and greenness.</p></div>