Study Links Benzene, Formaldehyde, TCE to Cancer
The International Agency for Research on Cancer (IARC) classifies benzene, formaldehyde and tricholorethylene (TCE) as carcinogenic to humans. Many manufacturing and production industries use these three chemicals, which are also commonly present in the environment. Scientists around the world are researching exactly how these chemicals cause cancer.
A study published on May 2, 2016 in the journal Carcinogenesis examined blood and urine samples from chemical-exposed Chinese factory workers. The researchers looked for changes to the workers’ blood, lymph cells and DNA often seen as non-Hodgkin’s lymphoma (NHL) and myeloid leukemia precursors.
The study, “Comparison of hematological alterations and markers of B-cell activation in workers exposed to benzene, formaldehyde and trichloroethylene (Bassig,)” found significant white blood cell and lymphocyte count decreases in workers exposed to all three chemicals. Bassig said the chemicals’ toxic effects on human blood and lymph cells “provide insight into their distinct patterns of toxicity and provide some mechanistic support for the chemical-specific associations with particular hematological cancers.”
The scientists studied workers from three separate Chinese regions. They examined Tianjin workers for benzene, Guangdong workers for TCE, and other unrelated Guangdong workers for formaldehyde. The studied subjects wore sensors recording their chemical exposure during their work shift. Scientists also studied the workers’ blood and post-shift urine.
The scientists found significantly decreased white blood cell counts in workers exposed to all three chemicals, compared with unexposed workers. Benzene-exposed workers saw white blood cell count decreases proportional to their exposure levels, while TCE-exposed workers only exhibited noticeable white blood cell drops for exposure equal to or more than 12 parts per million. Formaldehyde-exposed workers showed a significant white blood cell count decline compared to unexposed workers.
Blood tests showed TCE-exposed workers suffered no myeloid cell decline. However, benzene- and formaldehyde-exposed workers showed significant declines. Granulocytes and platelets declines increased proportionally according to benzene exposure.
Chemically-exposed workers exhibited marked decreases in lymphoid cells. Researchers found statistically significant decreased lymphocyte counts in workers exposed to all three chemicals, with exposure-dependent increases observed in benzene-exposed workers.
The researchers also found plasma level reductions in chemically-exposed workers, as well as increased instances of partial chromosomal deletion. Scientists frequently find that deletion, known as “monosomy 7,” in the bone marrow of myelodysplasia and acute myelogenous leukemia patients.
Bassig said altered white blood cell, myeloid cell and lymphoid cell levels are commonly related to blood cancers.
“Given that alterations in myeloid and lymphoid cell types have been associated with hematological malignancies, our data provide biologic insight into the epidemiological evidence linking exposure to benzene and [formaldehyde] with risk of myeloid leukemia, and TCE and benzene with risk of lymphoid malignancies,” Bassig said.
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 acute myeloid leukemia, myelodysplastic syndrome, and non-Hodgkin’s lymphoma. Benzene is also commonly found in car exhaust and cigarette smoke. Benzene is used to increase gasoline’s octane rating, though concerns over groundwater leakage forced its regulation.
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, printers, rubber workers, shoe makers, laboratory technicians and gas station employees.
Formaldehyde is a colorless, flammable chemical used in building materials and to produce several household products. It is most popularly known as a preservative in mortuaries and medical laboratories. It is also used in pressed-wood products including particleboard, plywood and fiberboard. It is further used in glues, adhesives, permanent-press fabrics, paper product coats, and certain insulation materials.
According to the U.S. Consumer Product Safety Commission, most Americans are exposed to formaldehyde via pressed-wood products used in homes. Cigarette smoke can be a source, as well as the use of unvented fuel-burning appliances including gas stoves, wood burning stoves and kerosene heaters.
Tricholoroethylene (TCE) was first produced in the 1920s as a solvent for organic materials. It was first used to extract vegetable oils from plant materials, as well as coffee decaffeination and preparing flavoring extracts. It was later used as an anesthetic and as a cleaning solvent. Presently, it is most commonly used as a metal degreaser.
If you believe your recent cancer diagnosis might be related to exposure to benzene, formaldehyde or tricholoroethylene, 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.