Study: Work Exposure to Benzene Increases NHL Risk
Certain Occupations At Higher Risk of Benzene Cancer
Several agencies, including the U.S. Environmental Protection Agency (EPA) and the International Agency for Research on Cancer (IARC) have classified benzene as carcinogenic to humans. Many scientific studies have examined the link between benzene exposure and the development of non-Hodgkin’s lymphoma (NHL).
Benzene exposures can and do occur at work for many occupations. An October 2015 study published in the scientific journal Environmental Health Perspectives demonstrated a clear connection between occupational benzene exposure and the development of NHL.
The study, “Occupational Exposure to Benzene and Non-Hodgkin Lymphoma in a Population-Based Cohort: The Shanghai Women’s Health Study (Bassig),” examines benzene-exposed women’s health outcomes.
The Shanghai Women’s Health Study involved 74,942 urban Shanghai women age 40 through 70 who enrolled in the study between December 1996 and May 2000. Trained personnel interviewed the women and presented them with a lifetime occupational history questionnaire assessing job title, workplace name, type of business, their specific work tasks, and employment dates for all jobs lasting more than a year.
Other components of the questionnaire included residential history, personal lifestyle habits, and medical history.
Researchers cross-referenced the questionnaires with annual checks of the Shanghai Cancer Registry of all newly diagnosed cancer cases. Researchers also conducted follow-up surveys with the women every 2 to 3 years collecting disease and hospital information.
Scientists assessed benzene concentrations by monitoring job exposure matrices (JEMs). A job exposure matrix assesses health hazard exposures in occupational health studies. Scientists build JEMs by measuring chemical exposures in various occupations and industries and collating the information, in the hope of using the aggregated data to create a reliable exposure database. Scientists collect and verify exposure data and add it to the JEM, thus increasing its overall accuracy and reliability.
The Bassig researchers measured benzene concentration in Shanghai factories and compared them against the JEM databases. They also used short-term air measurement data collected by the Shanghai Centers for Disease Control.
The researchers found occupational benzene exposure in 15% of the 73,087 total participants. Of those exposed, 85% had no occupational benzene exposure during the 4-year enrollment period. The benzene-exposed employees predominantly worked in the rubber products (13%), organic chemicals (10%), motor vehicles (8%), miscellaneous electronics (7%) and TV and audio equipment (6%) manufacturing industries.
The article states “We found evidence for an increased risk of NHL for women ever exposed to benzene and for those with higher cumulative exposure levels and durations of occupational benzene exposure. Our findings are consistent with several previous studies that have found an elevated risk of NHL overall or of specific NHL subtypes associated with benzene exposure, and they provide additional evidence that occupational exposure to benzene is associated with NHL risk.”
The Bassig study notes women exposed to benzene were significantly more likely to develop NHL than women who weren’t exposed. Their findings correlated elevated benzene exposure to NHL development, as those women with higher exposures had a significantly increased NHL risk than those with the least exposure.
“We observed that women who were ever exposed to benzene had a significantly higher risk of NHL compared with unexposed women,” Bassig said. “Significantly increased risks were also observed among women in the highest two tertiles of exposure duration and cumulative exposure.” A tertile is one-third (33.33%) of a given population.
Non-hodgkin’s lymphoma is a cancer starting in the white blood cells called lymphocytes. Bassig said previous studies also connect benzene exposure to chronic and acute lymphoblastic lymphoma, two NHL subtypes.
Benzene is an aromatic hydrocarbon compound used in the manufacture of plastics, resins and dyes. Numerous scientific studies detail benzene’s various adverse health effects, including its ability to cause acute myeloid leukemia, myelodysplastic syndrome, and non-Hodgkin’s lymphoma. Benzene is a component often found in solvents, industrial oils, paints and other petrochemical products.
Industries most commonly linked to benzene exposure include petrochemical manufacturing, petroleum refining, coke and coal chemical manufacturing, rubber tire manufacturing, gasoline storage, shipment and retail operations, plastics and rubber manufacturing, and shoe manufacturing.
Occupations particularly vulnerable to benzene exposure include steel workers, painters, mechanics, printers, rubber workers, shoe makers, laboratory technicians and gas station employees.
If you believe your recent non-Hodgkin’s lymphoma diagnosis might be related to benzene exposure, please contact the trial attorneys of Allen Stewart, P.C. The firm has decades of combined experience in helping those who have developed cancer due to toxic exposure.