This article was produced in partnership with The Times-Picayune and The Advocate, which is a member of the ProPublica Local Reporting Network. ProPublica is a nonprofit newsroom that investigates abuses of power. Sign up to receive our biggest stories as soon as they’re published.

Environmental groups had been waiting nearly three years for the U.S. Environmental Protection Agency to comply with a federal judge’s orders to update Clean Air Act rules governing emissions of various toxic chemicals.

The agency finally proposed those new rules last week, saying they would reduce emissions of ethylene oxide, a carcinogen that the EPA recently determined is more dangerous than the agency once believed.

But interviews and records show that the new rules, if implemented, would scarcely make a dent in emissions of the cancer-causing pollutant. The rules call for annual airborne emissions of ethylene oxide to be reduced by 10 tons nationwide, which would represent a roughly 7% reduction from the 140.7 tons that chemical plants emitted in 2018.

That reduction would barely make up for the ethylene oxide that’s likely to be emitted by a planned Formosa Chemicals plant in St. James Parish, which according to permitting documents will release up to 7.7 tons of the carcinogen into the atmosphere each year. The plant is scheduled to be built by 2022.

The proposed rule change comes as the Mississippi River corridor between Baton Rouge and New Orleans is experiencing a dramatic expansion of petrochemical facilities, and with it an increase in the toxic emissions they produce. A recent analysis by ProPublica and The Times-Picayune and The Advocate show that many of the new plants, like the Formosa facility, are being built in communities that already have very high concentrations of toxic chemicals.

Get Our Top Investigations Subscribe to the Big Story newsletter.

Ethylene oxide is used in the manufacture of a number of other chemicals, including ethylene glycol, which is used as an antifreeze. Louisiana has 13 plants that emit ethylene oxide in sufficient amounts that they must report it to the Toxics Release Inventory, a database maintained by the EPA. Eleven of the 13 plants are between Baton Rouge and New Orleans, while the other two are near Lake Charles. Between them, the Louisiana plants in 2018 released 27.8 tons of ethylene oxide, about one-fifth of the total produced nationwide.

The new rules will only affect parts of two of those 13 plants, according to the EPA. Officials with the Louisiana Department of Environmental Quality dispute that, saying only one plant in the state will be affected. Regardless of which agency is correct, the reason is that the new rules apply only to a small subset of processes and equipment used at American chemical plants, and those processes and equipment account for a small proportion of the total amount of ethylene oxide produced.

According to the EPA, the Louisiana plants that would be affected are two of the state’s largest producers of ethylene oxide: BASF’s plant in Geismar and Dow Chemical’s plant in Plaquemine. In 2018, BASF reported 7.6 tons of ethylene oxide emissions, while Dow reported 1.5 tons in Plaquemine.

It’s unclear whether the proposed rules would have any effect on the planned Formosa plant. A spokeswoman for Formosa said that they would not and that the amount of the chemical that Formosa releases will be within the standards DEQ says will protect human health and the environment.

But Maggie Sauerhage, a spokeswoman for the EPA, said federal officials believe that the proposed Formosa plant may be affected by the new rules, although she said more information is needed.

Corinne Van Dalen, an Earthjustice attorney representing residents opposed to the plant, said a review of Formosa’s permit requests indicate at least five of its 16 facilities would fall under the rule, but not the two that would emit ethylene oxide.

By 2022, when Formosa’s 16 facilities are scheduled to be operational, its permits would allow the release of 800 tons of toxic air pollutants each year, which would double the parish’s current emissions. In 2017, St. James ranked ninth among Louisiana’s 64 parishes and among the top 100 counties in America for toxic air emissions.

The new rules were drafted in response to a March 2017 order by a federal judge in Washington, D.C., who ruled that the EPA had for years illegally delayed updating its rules requiring pollution reductions under the Clean Air Act. The order gave the EPA three years to comply.

According to the federal Occupational Safety and Health Administration, acute exposures to ethylene oxide may result in respiratory and lung problems, headache, nausea, vomiting, shortness of breath and other health issues. Chronic exposure has been associated with birth defects, mutations, brain damage and allergic reactions to chemicals, in addition to cancer. In announcing the new rules, the EPA called current ethylene oxide emissions “unacceptable” and confirmed concerns that the chemical is more dangerous than previously thought — with exposure to even small amounts linked to several types of cancer.

Last year, the agency released a National Air Toxics Assessment report that said one census tract in St. Charles Parish near the Union Carbide plant there — owned by Dow — faced the highest risk in the country of developing lymphoid or breast cancers because of exposure to ethylene oxide emitted by the plant.

The assessment, as well as increased awareness of the risks posed by ethylene oxide, has focused new attention on the plants that make it. Early this year, Illinois officials ordered the temporary closure of a controversial plant in the Chicago suburbs that emitted large amounts of the chemical. The company, Sterigenics, announced in September the plant would be closed permanently.

The assessment also prompted DEQ officials to ask Dow for information about its plans to reduce ethylene oxide emissions at the Union Carbide plant.

Look Up an Address In a Notoriously Polluted Area of the Country, Massive New Chemical Plants Are Still Moving In Data from an EPA model indicates that communities along the lower Mississippi River corridor already face severely elevated cancer risks from industrial activity. Massive new chemical plants are slated to be built there anyway.

In January, the company told the agency that the EPA’s risk assessment was flawed because it was based on an initial estimate from Dow that its St. Charles Parish plant had released 15.03 tons of the carcinogen in 2014. In fact, Dow said, it only released 10.35 tons of the chemical that year, resulting in less risk of cancer than what the EPA found.

In its letter, Dow said a 2016 project that reduced vapor emissions during the loading of rail cars had also lowered ethylene oxide emissions at the plant by 2.64 tons a year. According to the company’s 2018 Toxics Release Inventory report, the most recent available, it released under 4 tons of the chemical in St. Charles Parish last year.

A DEQ spokesman said Dow’s Union Carbide plant was among 31 state facilities that received letters last November requesting that they review ways to reduce their ethylene oxide emissions.

According to the Toxics Release Inventory database maintained by the EPA, the largest emitters of ethylene oxide in Louisiana last year were the Sasol Chemicals facility in Lake Charles, with 8.4 tons; BASF in Geismar, with 7.6 tons; Shell Chemical in Geismar, with 5.2 tons; the Union Carbide plant, with 4 tons; and Dow’s Plaquemine chemical facility, with 1.5 tons.

DEQ spokesman Gregory Langley said only one company other than Dow responded to the letters.

That company, Georgia-Pacific, told the state that its Port Hudson facility was permitted to release only 20 pounds of the chemical a year, and that its actual rate of release was only about 2 pounds a year.

Kim Cusimano, a spokeswoman for Sasol, said testing this year of an ethylene oxide control device at its plant indicated the company has been dramatically overestimating its emissions of the chemical. Cusimano said the company now believes its 2018 reported emissions should have been reduced by 95%.

The proposed EPA rules must still be published in the Federal Register and will then be subject to a 45-day public comment period.

The suit prompting the order was filed in 2015 against the EPA by nine environmental groups, including the Louisiana Bucket Brigade of New Orleans and the Louisiana Environmental Action Network, based in Baton Rouge. The groups charged that the EPA had failed to update 20 sets of Clean Air Act regulations, including the one dealing with ethylene oxide, which had not been adjusted since 2003, even though the EPA was required to adjust them at least every eight years.

The proposed rules change would also result in a reduction of 106 tons a year for other hazardous chemicals, including toluene, methanol, xylene, hydrogen chloride and methylene chloride. The federal government says all those substances also can cause cancer, as well as other adverse health effects including irritation of the lungs, eyes and mucous membranes, and effects on the nervous system.

The EPA says the current estimated risk of cancer from inhalation of ethylene oxide and associated chemicals is 2,000 for every 1 million people exposed, well above the agency’s goal of reducing the risk to no more than 100 per 1 million exposed.

However, an attorney for Earthjustice, a nonprofit organization that represented the environmental groups in the lawsuit, said the proposed rules will still allow industries to release ethylene oxide in amounts that would result in 200 to 300 cancer cases per 1 million people exposed — two or three times the agency’s targets.

Earthjustice attorney Emma Cheuse noted the rules also continue to allow releases of ethylene oxide resulting from so-called force majeure incidents, including some accidents and major storms, such as hurricanes.

“Communities in the Gulf states need protection every day, not just on sunny days,” Cheuse said.

The new rules also do not require the installation of fenceline monitoring stations that could independently determine if the companies are complying with the reduction requirements, she said. Such fenceline monitoring already has been required in the Los Angeles area by the local South Coast Air Quality Management District, but it has not been required for many plants in Louisiana.

Read More Welcome to “Cancer Alley,” Where Toxic Air Is About to Get Worse Air quality has improved for decades across the U.S., but Louisiana is backsliding. Our analysis found that a crush of new industrial plants will increase concentrations of cancer-causing chemicals in predominantly black and poor communities.

And Anne Rolfes, founding director of the Louisiana Bucket Brigade, said she doesn’t believe it when companies say that because they’re following state regulations, their emissions do not threaten local residents.

“Formosa is a serial polluter,” she said, pointing to a court settlement reached by Formosa Plastics in Texas, where the company agreed to tighter wastewater discharge standards and to pay $50 million to settle allegations that the company has spilled tons of plastic pellets into waterways near the Gulf of Mexico. “We have no confidence in any of the company’s modeling, in any of its air monitoring or in any of its promises to abide by the law.”

Officials with Formosa’s Texas plant, however, insisted that they will abide by the terms of the settlement and federal environmental laws.

“The conditions agreed to in this settlement demonstrate Formosa’s commitment to manufacturing our products in a safe and environmentally friendly manner,” Ken Mounger, executive vice president of the Texas facility, said when the settlement was announced. “We will continue to partner with local communities and stakeholders to ensure that FPC USA environmental programs are at the top of our industry.”