Residence in proximity of petrol stations and childhood leukemia risk

Background Air pollutant concentrations close to petrol stations tend to increase, especially for benzene and other carcinogenic contaminants, depending on meteorological factors, features of nearby buildings and station activity. For this reason, it is suggested that petrol stations increase the risk of cancer, in particular, childhood leukemia. Methods/Approach We carried-out a population-based case-control study in two Northern Italy provinces, Modena and Reggio Emilia. We included 182 cases of childhood leukemia diagnosed in the period 1998-2019, and 726 age and sex-matched controls. We geocoded child residence and the 790 petrol stations located in the study area, of which we retrieved the annual refueling activity. Exposure was assessed based on both residential distance from the nearest petrol station and on the activity of all plants located up to 1000 m from the home. Risk ratio of leukemia was estimated by computing disease odds ratio (OR) through conditional logistic regression models adjusted for potential confounders. Results We found an increased risk for childhood leukemia associated to residence in close proximity to petrol stations. Compared to those who live ≥ 1000m, OR was 2.30 (95% CI 0.53-9.97) for children living <50 m from nearest petrol station in bivariate analysis and 2.16 (95% CI 0.49-9.42) in multivariable analysis. The excess risk was higher when considering acute lymphoblastic leukemia (ALL) subtype (OR=2.83, 95% CI 0.61-13.21), and in children diagnosed after 5 years of age (OR=4.68, 95% CI 0.61-35.95) compared with < 5 years (OR=1.63, 95% CI 0.14-18.84). Conclusions Our study found an increased childhood leukemia risk for residence in close proximity (<50 meters) to a petrol station. Such excess risk was higher for the ALL subtype and for children diagnosed after 5 years.