What is benzene? Is it a carcinogen?

Exposure routes: Inhalation, skin contact, and oral ingestion are the most toxic and dangerous routes.

Where found: Benzene is an industrial chemical that is widely used as a solvent and used in inks, rubber, lacquers, paint removers, gas additives, glue backing for carpeting, high-solvent paints, some furniture wax, automobile exhaust, tobacco smoke, secondhand smoke, taxidermy, firefighting, metal preparation and pouring, petroleum refining, industrial cleaning, drinking water, and closed processes to synthesize organic chemicals. It is also used to make dyes and insecticides and in the processing of numerous chemicals.

At risk: Children and pregnant woman are at higher risk. However, anyone exposed to benzene is at risk. For example, the presence of benzene in gasoline makes exposure to it a risk for anyone filling an automobile gas tank.

Etiology and symptoms of associated cancers:According to the American Cancer Society, benzene causes chromosomal damage to the bone marrow, the blood-forming tissue, which can then lead to leukemias and lymphomas. The US Centers for Disease Control and Prevention reported in 2013 that benzene can also cause insufficient red blood cell production and alter antibody levels. Exposure to as little as less than one part per million can lower white blood cell counts, as reported in a 2004 study by Qing Lan et al. in the journal Nature.

Symptoms of leukemias and lymphomas include fever, night sweats, fatigue, bleeding and easy bruising, bone pain, frequent infections, swollen lymph nodes, and weight loss.

History: Benzene is a natural component of crude oil. In 1825 Michael Faraday performed distillation experiments and extracted a gas from the oil. The gas burned, and he named it “bicarburet of hydrogen.” The chemical structure of benzene remained elusive until 1865, when Friedrich August Kekulé von Stradonitz hypothesized a hexagonal structure.

Benzene was derived from the distillation of coal by A. W. Hoffman in 1846. The uses of and demand for benzene increased along with oil exploration as its usefulness in many industrial applications became apparent.

Linus Pauling, the Nobel Prize–winning physicist, was one of many scientists to attempt to elucidate the unique hybrid structure of benzene that was confirmed in 1931.

The main use of benzene prior to World War I was in gasoline blending, as it increased octane. It was used extensively in industry in World War II, and almost all organic chemistry–related industry involves petroleum (benzene-containing) products.

"Benzene." Cancer.org. Amer. Cancer Soc., 9 Dec. 2013. Web. 4 Sept. 2014.

Chilcott, R. P. HPA Compendium of Chemical Hazards: Benzene. Health Protection Agency, 2011. PDF file.

"Facts about Benzene." CDC.gov. Centers for Disease Control and Prevention, 14 Feb. 2013. Web. 4 Sept. 2014.

Lan, Qing, et al. "Hematotoxicity in Workers Exposed to Low Levels of Benzene." Nature 306.5702 (2004): 1774–76. PDF file.

Snyder, Robert. "Leukemia and Benzene." International Journal of Environmental Research and Public Health 9.8 (2012): 2875–93. PDF file.

US Department of Health and Human Services, Public Health Service, National Toxicology Program. 12th Report on Carcinogens. Research Triangle Park: US Dept. of Health and Human Services, 2011. Print.