In a new study, researchers from India compared immune system damage between 428 gasoline pumping workers and 78 unexposed individuals.  They found a significant increase in the concentration of benzene and its byproducts in both blood and urine in the workers.

Levels of Reactive Oxygen Species and Malondialdehyde were significantly elevated, and Glutathione and total superoxide dismutase were decreased in the workers compared with the controls. A statistically significant decrease in the immunoglobulin levels, CD4T cells, CD4/CD8 ratio was also observed in the workers and p53 gene expression was markedly higher in the workers.  The investigators concluded that occupational exposure to benzene causes oxidative stress, immune suppression and increases the expression of tumor-suppressing gene p53 in gasoline filling workers.  This study adds to the body of literature that gasoline pump workers have increased risks of immunologic damage and cancer from exposure to benzene in gasoline.

Uzma, N., et al., “Exposure to benzene induces oxidative stress, alters the immune response and expression of p53 in gasoline filling workers,” Am. J. Ind. Med. advance pub. (Sept. 30, 2010).