Ethylene oxide is 30 times more likely to cause certain cancers than scientists had once thought.

Originally published by Bloomberg Environment by Amena H. Saiyid

  Chemical plants in Louisiana and Texas release far more of the cancer-causing ethylene oxide gas than the Sterigenics medical sterilizer plant in Illinois, which snagged national headlines this year and was shut down by state regulators.

The Environmental Protection Agency decided in late 2016 that the gas is much more dangerous than previously thought—an assessment that industry groups and some state regulators dispute. A separate federal report found that emissions from the Sterigenics medical sterilizer plant in Willowbrook, Ill. could be harmful to public health.

The report sparked a local and national outcry that ultimately led the Illinois Environmental Protection Agency to shut down the Sterigenics plant in February, after further air quality testing, and led Illinois in June to pass the nation’s toughest ethylene oxide laws.

But a Bloomberg Environment analysis of the U.S. EPA’s air toxic emissions data shows that the top 10 ethylene oxide emitters in the nation were actually chemical plants in Louisiana and Texas. Dow Inc.'s sprawling 2,000-plus-acre Union Carbide Corp. petrochemical complex in Louisiana’s St. Charles Parish topped the ranking, followed by Huntsman Corp.'s chemical plant in Port Neches, Texas, according to the 2014 data, the latest available.


In fact, the analysis showed the St. Charles chemical plant released more than five times as much ethylene oxide as the Sterigenics plant southwest of Chicago, and the Port Neches plant emitted nearly four times that quantity. The Illinois plant from Sterigenics, a unit of Sotera Health LLC, ranked 16th on the list.

But the chemical plants in Louisiana and Texas have not received the same sort of investigation or monitoring from either the states or the federal government, and lawmakers from those states appear unaware of the issue.

“EPA needs to do its job here, or they’ll be leaving the residents of St. Charles Parish and other communities exposed to intolerable health risks,” said Eric Schaeffer, executive director for the nonprofit Environmental Integrity Project.

Emissions from all the facilities on the EPA’s list, including the Union Carbide, Huntsman, and Sterigenics plants, are within legal limits under complex Clean Air Act rules, which set different standards for facilities under different industrial classifications.

After determining the chemical is far more dangerous than previously thought, the EPA is now reconsidering emission limits for the two main industrial sources of ethylene oxide: commercial medical sterilizers and manufacturers of miscellaneous organic chemicals.

Some lawmakers and state regulators, especially those from Illinois, want the EPA to act faster. Sen. Tammy Duckworth (D-Ill.), who spearheaded the congressional campaign to push the EPA to update standards for commercial sterilizers, said in an interview that she has asked EPA to monitor ethylene oxide monitoring at all plants, and to look at “updating the standards.”

Schaeffer, who worked in EPA’s enforcement office from 1990 to 2002, including as director of civil enforcement, said the current standards were based on research performed in the 1980s.

“EPA’s own research concluded in 2016 that ethylene oxide is far more dangerous than previously understood. Because EPA hasn’t updated its standards, people downwind are left to breathe potentially dangerous amounts of a chemical that increases the risk of cancer,” he said.

30 Times More Carcinogenic

Ethylene oxide is a flammable, colorless gas with a faintly sweet odor that is used to sterilize medical equipment, and also as a building block for other chemicals to make a range of products, including antifreeze, textiles, plastics, detergents, and adhesives.

The gas is found naturally in ambient air. But prolonged exposure to higher concentrations can hurt eyes and lungs, harm the brain and nervous system, and potentially cause lymphomas, leukemia, and breast cancer.

The EPA concluded in late 2016 that ethylene oxide is at least 30 times more carcinogenic than previously understood.

Facilities that release ethylene oxide are spread around the country, with many lower-emitting sites in states like Minnesota and North Carolina. But the 2014 data showed that those with the highest annual emissions were often concentrated further south; 12 of the top 20 highest-emitting facilities were in Louisiana and Texas.

But the EPA’s latest National Air Toxics Assessment showed the cancer risk from ethylene oxide in Louisiana’s St. Charles Parish, location of the Union Carbide plant, is more than three times the cancer risk facing people near the Sterigenics facility in Illinois’ DuPage County. The cancer risk near Huntsman’s Port Neches plant is slightly lower than Sterigenics’, but still higher than the EPA’s safe level. 

Yet regulators from Texas and Louisiana have been slow to act. The Texas Commission on Environmental Quality said the agency “believes the current standards are protective of human health and the environment.”

The Louisiana Department of Environmental Quality said it is working with the EPA to address concerns about ethylene oxide. At the same time, the agency is considering permits for Taiwan’s Formosa Plastics Corp. to build a $9.4 billion plastics complex in St. James Parish, which would be allowed to release up to 7 tons of ethylene oxide a year.

Many residents oppose the “Sunshine Project,” which would be a mile from an elementary school. St. James Parish is bordered to the north by Ascension Parish, home to petrochemical plants owned by BASF Corp. and Shell Chemical, which were the fifth-highest and ninth-highest emitters of ethylene oxide in the nation. Shell Chemical is the petrochemicals arm of Royal Dutch Shell Plc. 

Gregory Langley, spokesman for Louisiana’s environmental quality department, said the state’s regulators sent letters and met with some facilities permitted to emit ethylene oxide in the state, to ask them to develop strategies to lower their emissions and make sure they report emissions accurately. Langley added that “LDEQ is early in the process but will continue to work with EO emitting facilities and EPA to develop a path forward.” 

Dow Inc., which owns Union Carbide and its facility in Louisiana, said its plants comply with current EPA regulations and that it is continuing to reduce ethylene oxide emissions as part of its sustainability goals.

“In fact, between 2014 and 2017, emissions at Union Carbide have decreased drastically, approximately 50%, due to improvements Dow has made at the site,” Ashley Mendoza, Dow spokeswoman, said in an email.

You may not be able to control your outdoor air, but you can control your indoor air. Investing in an air purifier with a heavy duty carbon filtration system like the Airpura C600DLX can significantly reduce the amount of ethylene oxide in your breathing air.