Childhood Lymphohematopoietic Cancer Incidence and Hazardous Air Pollutants in Southeast Texas, 1995-2004

• Published in: Environmental health perspectives Vol. 116; no. 11; pp. 1576 - 1580
• Main Authors: Whitworth, Kristina W., Symanski, Elaine, Coker, Ann L.
• Format: Journal Article
• Language: English
• Published: United States National Institute of Environmental Health Sciences. National Institutes of Health. Department of Health, Education and Welfare 01.11.2008; National Institute of Environmental Health Sciences
• Subjects: Adolescent; Adult; Air pollutants; Air Pollutants - toxicity; Air pollution; Benzene; Cancer; Cancer incidence; Census; Census tracts; Censuses; Child; Child, Preschool; Childhood; Children; Children's Health; Confidence intervals; Diagnosis; Ecological monitoring; Elevated; Environmental agencies; Environmental aspects; Estimates; Female; Hazardous; Health; Health aspects; Humans; Incidence; Leukemia; Leukemia in children; Leukemias; Male; Mathematical models; Myeloid leukemia; Pollutants; Precursor Cell Lymphoblastic Leukemia-Lymphoma - epidemiology; Race; Regression; Regression analysis; Risk; Risk factors; Social Class; Texas - epidemiology; United States; United States Environmental Protection Agency; United States; Texas; USA, Texas, Houston; USA, Texas; hazardous air pollution; epidemiology; childhood cancer; air toxics; 1,3-butadiene; benzene
• ISSN: 0091-6765; 1552-9924
• DOI: 10.1289/ehp.11593

Background: Cancer is the second leading cause of death among U.S. children with few known risk factors. There is increasing interest in the role of air pollutants, including benzene and 1,3-butadiene, in the etiology of childhood cancers. Objective: Our goal was to assess whether census tracts with the highest benzene or 1,3-butadiene ambient air levels have increased childhood lymphohematopoietic cancer incidence. Methods: Our ecologic analysis included 977 cases of childhood lymphohematopoietic cancer diagnosed from 1995-2004. We obtained the U.S. Environmental Protection Agency's 1999 modeled estimates of benzene and 1,3-butadiene for 886 census tracts surrounding Houston, Texas. We ran Poisson regression models by pollutant to explore the associations between pollutant levels and census-tract cancer rates. We adjusted models for age, sex, race/ethnicity, and community-level socioeconomic status (cSES). Results: Census tracts with the highest benzene levels had elevated rates of all leukemia [rate ratio (RR) = 1.37; 95% confidence interval (CI), 1.05, 1.78]. This association was higher for acute myeloid leukemia (AML) (RR = 2.02; 95% CI, 1.03-3.96) than for acute lymphocytic leukemia (ALL) (RR = 1.24; 95% CI, 0.92-1.66). Among census tracts with the highest 1,3-butadiene levels, we observed RRs of 1.40 (95% CI, 1.07-1.81), 1.68 (95% CI, 0.84-3.35), and 1.32 (95% CI, 0.98-1.77) for all leukemia, AML, and ALL, respectively. We detected no associations between benzene or 1,3-butadiene levels and lymphoma incidence. Results that examined joint exposure to benzene and 1,3-butadiene were similar to those that examined each pollutant separately. Conclusions: Our ecologic analysis suggests an association between childhood leukemia and hazardous air pollution; further research using more sophisticated methodology is warranted.