Occupational exposure to solvents and acute myeloid leukemia: A population-based, case-control study in four nordic countries

Objective The aim of the current study was to assess the relation between occupational exposure to solvents and the risk of acute myeloid leukemia (AML). Methods Altogether, this study comprises 15 332 incident cases of AML diagnosed in Finland, Norway, Sweden, and Iceland from 1961-2005 and 76 660 controls matched by year of birth, sex, and country. Occupational records were linked with Nordic Occupational Cancer Study job exposure matrix (JEM) to estimate quantitative values for 26 occupational exposure factors. Hazard ratios (HR) with 95% confidence intervals (95% CI) were estimated by using conditional logistic regression models. Results We did not observe statistically significantly increased risk for exposure to any of the solvents. HR estimates for high levels of toluene (HR 1.35, 95% CI 0.74-2.46), aromatic hydrocarbon solvents (ARHC) (HR 1.18, 95% CI 0.76-1.86), and moderate-to-high levels of trichloroethylene were slightly but non-significantly elevated. We did not observe an association between benzene exposure and AML in this study. Conclusions This study did not provide clear evidence for an association between occupational solvent exposure and AML. There was some indication for an excess risk in the groups of workers exposed to toluene, trichloroethylene, and ARHC.