Benzene is one of the most commonly produced and most toxic chemicals in the U.S. Photo: Stephanie Young Merzel.

What is benzene?

November 1st, 2019

Benzene is one of the most commonly produced and most toxic chemicals in the U.S. Photo: Stephanie Young Merzel.

  • By Allyn West

Kathryn Ament was having a margarita on the patio of a restaurant in Webster when she noticed a sudden strong, sweet smell. She waved at the air in front of her nose. What was that?, she wondered.

It was a mixture of petrochemical products, including benzene.

Two hours earlier, a tanker had crashed into two barges near the Barbours Cut Terminal in the Houston Ship Channel, about 18 miles away.

One barge capsized, and the other was damaged, dumping into the water about 11,000 pounds of reformate, which is used to make gasoline, and causing that noxious mixture to plume out and over Bay Area neighborhoods.

Later that night, at 10:30 p.m., a contractor hired by the Texas Commission on Environmental Quality “detected 2,400 to 2,600 parts per billion of benzene” in Seabrook — a level 14 times higher than what the agency says can harm our health, the Houston Chronicle reported.

When the TCEQ tweeted the next day that benzene levels were “still elevated,” someone tweeted back: “When we noticed a strong smell, we raced away in the truck. Had fumes that started making me feel sick.”

What is benzene?

Benzene — found in our air, water and soil, discovered at more than 1,000 of the EPA’s list of the 1,684 most seriously hazardous waste sites — is one of the most toxic and most commonly produced chemicals in the U.S.

Though benzene is a byproduct of cigarette smoke and exhaust from gasoline-powered trucks and cars — and even comes from forest fires and volcanic eruptions — it’s produced almost exclusively from crude oil and coal during heavy industrial processes — turning coal into coke and refining oil down into a range of consumer products, including Styrofoam, solvents, detergents, inks, dyes, resins, synthetic fibers, lubricants, drugs and pesticides. It’s also used to make explosives.

Benzene, then, enters our bodies in a variety of ways — we can breathe it in, swallow it and absorb it through our skin. According to the Agency for Toxic Substances and Disease Registry, when we’re exposed to benzene, it can make our hearts beat too fast. It can cause headaches and nausea, drowsiness and dizziness, tremors and confusion. It can lead to unconsciousness. It can shrink ovaries, cause irregular menstruation and even pass through blood from a mother to her fetus.

Exposure for even five minutes to high levels of benzene — between 10,000 parts per million and 20,000 parts per million — can kill you.

Once benzene enters our bloodstream, it’s stored in our fat and bone marrow, where it can harm our blood and immune and nervous systems. Three independent agencies — the U.S. Department of Health and Human Services, the International Agency for Research on Cancer and the Environmental Protection Agency — have determined that benzene causes cancer, usually leukemia and aplastic anemia.

In 1948, the American Petroleum Institute concluded “the only absolutely safe concentration for benzene is zero.”

How does benzene impact our region?

Before that barge crash in May 2019, other disasters had created threats. In March, during the Intercontinental Terminals Company chemical fire, benzene levels became so elevated that residents of Deer Park and Galena Park were ordered to shelter in place and advised to shut down air-conditioners and jam blankets against doors and windows “to keep chemical vapors from entering.”

Then, in September, Tropical Storm Imelda caused the failure of floating roof tanks and other petrochemical equipment, leading to the unauthorized releases of more than 100,000 pounds of pollutants, including benzene, into the air.

That was an echo of the failures during Hurricane Harvey, when the city’s 311 line recorded complaints of headaches and dizziness during “dozens of calls from residents in Manchester about a strong gasoline smell,” the Houston Chronicle reported. Though TCEQ said that pollutants were “below levels of short-term health and/or welfare concern,” independendent testing by the city and the Environmental Defense Fund found benzene levels of “324 parts per billion — more than three times the level at which federal worker safety guidelines recommend special breathing equipment.

With so much of the petrochemical industry operating so near our homes, parks, schools and even restaurants, our region, from Port Arthur to Pasadena to Freeport, faces the risk of exposure to dangerous levels of benzene. And it is nowhere more risky than here on the Gulf Coast.

Data from the EPA’s Toxic Release Inventory in 2017 show that Texas alone was responsible for 35 percent of all the benzene emissions in the country — about 1.3 million pounds of it entering our air, water and soil. The next highest state was our neighbor, Louisiana, with 440,000 pounds.

What can we do about it?

As Dr. Elena Craft, senior director for climate and health at EDF, wrote in the Houston Chronicle after the barge crash, “Any exposure to benzene is too much.”

This summer, city officials piloted a new benzene alert system. The system is pulling data from fixed air monitors across Houston and automating an email when levels spike. Dr. Loren Hopkins, the city’s chief environmental science officer, said, “The quicker we identify benzene releases, the faster we put a stop to them.”

The alert system could help the health department locate the source of benzene and could also inform lawsuits against illegal polluters.

In October, TCEQ said it had spent $1.5 million to upgrade air monitoring equipment with a focus on the petrochemical industry. (Though the agency in 2007 relaxed the state’s long-term air pollution standards for benzene.)

Now, with 1.3 million pounds of that chemical being released in Texas and a growing plastics industry that could add dozens of new facilities in our region, even more sophisticated, real-time monitoring and oversight is necessary to protect our air and health. We need stronger enforcement of the laws we have and more frequent inspections of the facilities that could endanger us, Dr. Craft wrote.

And we need to appreciate just how dangerous benzene can be.

“If state leaders and TCEQ are serious about protecting public health," Dr. Craft wrote, "they must adopt more stringent and legally enforceable standards for the most harmful pollutants, starting with benzene.”

West is a senior communications specialist for the Environmental Defense Fund. Previously, he wrote for the Houston Chronicle, Rice Design Alliance and Swamplot. You can follow him on Twitter and Instagram.

Take Action

  1. Read the Center for Public Integrity's report on industry's denials of the risks of benzene
  2. Join hundreds of Texans and help #CleanUpTCEQ
  3. Add your name to the list of Houstonians wanting to protect our shared home

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