The role of residence near hazardous waste sites containing benzene in the development of hematologic cancers in upstate New York.

OBJECTIVES Epidemiologic studies suggest an association between environmental exposure to benzene and hematologic cancers, but the relationship is not firmly established. The aim of this study was to assess the potential association between residence near hazardous waste sites containing benzene and hospitalization discharge rates for persons having hematologic cancers. MATERIALS AND METHODS We determined the number of hospital discharges of people with hematologic cancers in New York State except for New York City for the years 1993 to 2008.Descriptive statistics and negative binomial regression models were used to compare the rates of hospitalization of residents in zip codes containing hazardous waste sites containing benzene to the rates of discharges from residents in zip codes without waste sites. RESULTS When adjusting for potential confounders we found a 15% increase in the rate of hospitalization for chronic lymphatic leukemia (CLL) [rate ratio (RR): 1.15; 95% confidence interval (CI): 1.00-1.33], a 22% increase in the rate of discharges for total leukemia (RR: 1.22; 95% CI: 1.04-1.43) and a 17% increase in the rate of discharges for total lymphoma (RR: 1.17; 95% CI: 1.02-1.35) in the benzene exposed sites. We found greater effects of exposure in African Americans compared to Caucasians, females compared to males and people with higher socioeconomic status (SES) compared to those with lower SES for several of the diseases studied. CONCLUSIONS After controlling for major confounders we found statistically significant increases in discharge rates for several hematologic cancers in persons residing in zip codes containing benzene waste sites. These results provide additional support for a relationship between environmental exposure to benzene and risk of hematologic cancers.