Center for Biological Diversity

For Immediate Release, September 1, 2017

Contact: Shaye Wolf, (415) 385-5746,

Analysis: Nearly 1 Million Pounds of Seven Deadly Air Pollutants Released by Texas Refineries During Harvey Floods

HOUSTON— Refineries and petrochemical plants in south Texas released nearly 1 million pounds of seven especially dangerous air pollutants during flaring and chemical spills triggered by Hurricane Harvey, according to a new Center for Biological Diversity analysis of industry data.

Staggering amounts of benzene, 1,3-butadiene, hexane, hydrogen sulfide, sulfur dioxide, toluene and xylene — estimated at 951,000 pounds so far — were emitted during Harvey-related flooding by several dozen petroleum industry facilities operated by Chevron Phillips, Exxon Mobil, Shell and other companies. These seven chemicals are all toxic air pollutants documented to cause serious harms to human health, and several cause cancer.

Total air pollutants from all oil and gas facilities added up to 5.46 million pounds, which is equal to 2,729 tons.

“Oil-industry facilities spewed thousands of tons of toxic chemicals into defenseless communities, despite ample warning about hurricane risk to this area,” said Shaye Wolf, the Center scientist who compiled the analysis. “Dangerous flaring from coastal refineries has become routine during major storms. The petroleum industry seems utterly unwilling to take responsibility for operating safely, even as climate change makes storms like Harvey more destructive.”  

Today’s analysis is based on initial industry reports to the Texas Commission on Environmental Quality through Aug. 31, and these numbers are expected to grow. While some of the toxic emissions were caused by storm damage, including tank roof failures at six facilities, the majority of emissions were caused by refinery and chemical plant shutdown and startup procedures that used flaring.

Below are the seven dangerous air pollutants released by Texas petroleum industry facilities during Harvey.

Seven Toxic Air Pollutants Released by Texas Oil Facilities During Harvey


Amount released

Human health risks



Increased cancer risk; harms to developing fetus; blood disorders; irritation to eyes, skin, lungs



Increased cancer risk; cardiovascular injury; irritation to eyes, skin, lungs



Neurotoxic effects including dizziness, nausea, headache, numbness, muscular weakness, blurred vision

Hydrogen sulfide


High concentrations can cause sudden unconsciousness, respiratory paralysis, seizures and death

Sulfur dioxide


Burning of the nose and throat, difficulty breathing, severe airway obstruction, particularly harmful to children, the elderly and those with asthma



Harms to the developing fetus; injury to central nervous system; irritation to eyes and lungs



Harms to nervous system, gastrointestinal system, cardiovascular system, kidneys and respiratory tract

A summary of the TCEQ data for these seven chemicals can be found here.

The Center for Biological Diversity is a national, nonprofit conservation organization with more than 1.5 million members and online activists dedicated to the protection of endangered species and wild places.

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