Parental occupational exposure to benzene and the risk of childhood and adolescent acute lymphoblastic leukaemia: a population-based study.

ObjectivesOnly a small number of studies have reported on the association of parental occupational exposure to benzene and risk of childhood and adolescent leukaemias. We examined associations with acute lymphoblastic leukaemia (ALL) in this population-based study in Denmark.MethodsBenzene was largely banned from Danish workplaces after 1975, thus this case-control study focused on the immediately prior years. Paediatric cancer cases (ResultsWe identified 217 employed case fathers and 169 employed case mothers, of which 22 (10.1%) and 11 (6.5%), respectively, were exposed to benzene (vs 6.7% and 2.9% of control fathers and mothers). Most exposed parents worked as machine or engine mechanics, or in the shoe industry. Maternal occupational exposure to benzene in pregnancy was related to increased risk of ALL in offspring (adjusted OR=2.28, 95% CI 1.17 to 4.41), while paternal preconceptional benzene exposure was not as strongly associated (adjusted OR=1.40, 95% CI 0.88 to 2.22).ConclusionsOur study supports an increased risk for ALL with parental occupational benzene exposure