Benzene, a key ingredient in gasoline, is a sweet-smelling chemical that is used to make plastics, lubricants, dyes and adhesives. It has also been suspected as a link to several blood disorders and cancers, specifically leukemia.
As the 17th-most produced chemical in the U.S., benzene can be found in cigarettes and car exhaust fumes. Before federal regulators set occupational exposure limits in 1987, benzene was a common solvent used in pure form by offshore workers and petrochemical industry workers.
Other workers who may be at risk are auto mechanics, gas station attendants and even printers because of the extended periods of time that they are exposed to the chemical.
Despite the exposure limit set nearly 30 years ago, Peter Infante, a former director of the office that reviews health standards at the Occupational Safety and Health Administration (OSHA), is adamant that benzene is still a danger, even in small doses.
“You’re still seeing elevated risks of leukemias and lymphomas among occupational groups exposed to benzene, as well as populations being polluted from these benzene sources,” Infante, who has studied benzene and its polluting effects for 40 years, told The Center for Public Integrity.
The National Institute for Occupational Safety and Health (NIOSH), part of the Centers for Disease Control and Prevention (CDC), recommends that workers limit their benzene exposure to an average of 0.1 ppm during a shift.
A study by the National Cancer Institute (NCI) published in 1997, reported workers in Shanghai, China, that had been exposed to benzene confirmed past research that suggested the chemical could be linked to the development of leukemia. The study also concluded: “The results of this study suggest that benzene exposure is associated with a spectrum of hematologic neoplasms and related disorders in humans. Risks for these conditions are elevated at average benzene-exposure levels of less than 10 ppm and show a tendency, although not a strong one, to rise with increasing levels of exposure. The temporal pattern of benzene exposure appears to be important in determining the risk of developing specific diseases.”
In 2001, the petrochemical industry decided to fund its own strategic Shanghai study, where BP, Chevron, ExxonMobil, ConocoPhillips and Shell Chemical forked out tens of millions of dollars toward the “Benzene Health Research Consortium,” a research effort lasting nearly a decade.
Although the study was funded by the petrochemical industry, researchers who participated in the work say the integrity of the study was not compromised, noting that all results – both favorable and unfavorable to the industry – were published in peer-reviewed journals.
In fact, Richard Irons, one of the study’s two principal investigators and now head of a consulting firm that does research for the petrochemical industry, said so far the research has confirmed benzene’s association with acute myelogenous leukemia (AML) as well as myelodysplastic syndrome (MDS), a cancer of the bone marrow.
Research is continuing to determine what association there may be between benzene and certain subtypes of AML and MDS, and possible links between the chemical and non-Hodgkins lymphoma, and at what level of exposure the chemical may pose a risk.