Estimating the proportion of childhood cancer cases and costs attributable to the environment in California

Objectives.To estimate the proportion of cases and costs of the most common cancers among children aged 0 to 14 years (leukemia, lymphoma, and brain or central nervous system tumors) that were attributable to preventable environmental pollution in California in 2013. Methods. We conducted a literature review to identify preventable environmental hazards associated with childhood cancer.We combined risk estimates with California-specific exposure prevalence estimates to calculate hazard-specific environmental attributable fractions (EAFs). We combined hazard-specific EAFs to estimate EAFs for each cancer and calculated an overall EAF. Estimated economic costs included annual (indirect and direct medical) and lifetime costs. Results. Hazards associated with childhood cancer risks included tobacco smoke, residential exposures, and parental occupational exposures. Estimated EAFs for leukemia, lymphoma, and brain orcentral nervoussystem cancer were21.3% (range = 11.7%-30.9%), 16.1% (range = 15.0%-17.2%), and 2.0% (range = 1.7%-2.2%), respectively. The combined EAF was 15.1% (range = 9.4%-20.7%), representing $18.6 million (range = $11.6 to $25.5 million) in annual costs and $31 million in lifetime costs. Conclusions. Reducing environmental hazards and exposures in California could substantially reduce the human burden of childhood cancer and result in significant annual and lifetime savings.