Aug. 18, 2004 -- Living next door to a gas station or auto repair shop may be associated with an increased risk of childhood leukemia, according to a new French study.
The problem might stem from exposure to benzene emitted by gas stations and auto repair businesses, write the researchers in the journal Occupational and Environmental Medicine. Previous studies have shown a clear association between the occupational exposure to benzene and acute leukemia in adults.
The association in children "could be due to chance, although the strength of the association and the duration trend are arguments for causal association," write the researchers.
The team of 11 scientists studied 280 children with acute leukemia and 285 children with other health problems at hospitals in four French cities: Nancy, Lille, Lyon, and Paris.
Of the children with leukemia, 40 had acute non-lymphocytic leukemia.
Acute lymphocytic leukemia is the most common type of leukemia in childhood and the most common type of childhood cancer in developed countries, but few risk factors have been identified for the disease.
More Exposure, More Risk
In the study, data were collected during face-to-face interviews with the children's mothers, asking specific questions about their career histories and where they lived during their pregnancies and after their children were born.
The researchers wanted to find out if the mothers' jobs they had while pregnant or homes were near high-traffic roads or adjacent to benzene emission sources like gas stations and auto repair shops.
There was no clear association between the mother's job during pregnancy and leukemia. Residential traffic density was also not associated with leukemia.
However, living next door to a gas station or car repair garage during childhood was associated with the risk of childhood leukemia.
Only a small number of children in the study were exposed to neighboring repair shops and gas stations. Still, there was significant trend in exposure duration among them, write the researchers. The longer a child lived by a gas station or car repair garage, the higher their risk seemed to be.
The association was particularly strong for acute non-lymphocytic leukemia, with 10% of cases found among children living near auto repair shops or gas stations.
The results held after screening out other possible risk factors, but they need confirmation by further studies, say the researchers.