New research shows link between benzene and non-Hodgkin lymphoma

Millions of people across the planet are exposed to benzene, a precursor for more complex chemicals used in the production of plastics, synthetic rubber, dyes, and other consumer products. In addition to being a significant component of gasoline, benzene has been detected in many household products, such as the surprising recent finding of benzene in popular sunscreens.

Although benzene has been known to cause leukemia, its relationship with non-Hodgkin lymphoma, a broad group of several closely related cancers, has been less clear. However, in a new paper in The Lancet Planetary Health, UC Berkeley School of Public Health researchers identify a statistically significant association between exposure to benzene and non-Hodgkin lymphoma.

The paper’s researchers, led by Iemaan Rana, MPH, PhD student at Berkeley Public Health and MD student at the University of Illinois College of Medicine—working with Professor Luoping Zhang, the principal investigator of the study—examined the potential link between benzene exposure and risk of non-Hodgkin lymphoma (NHL) by evaluating a wide array of previous studies, using the latest methods in electronic systematic review and meta-analysis.

The association they found was dose-dependent, meaning greater exposures to benzene yielded a higher risk of NHL. Because NHL comprises numerous cancers, the researchers tested whether benzene was more closely related to a particular subtype of NHL and uncovered a doubling of the risk for the diffuse large B-cell lymphoma subtype.

“The study sheds new light on our understanding of benzene as a carcinogen,” says Rana, “and provides compelling evidence that benzene not only causes leukemia, but also lymphoma.”

This paper is authored by Iemaan Rana, Sarah Dahlberg, Craig Steinmaus, and Luoping Zhang, all of Berkeley Public Health.