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Alabama environmental regulators have agreed to update standards used to limit the amounts of 12 toxic and carcinogenic substances in the state’s waterways, a move that clean water advocates say will help protect those who fish and swim in Alabama’s rivers.

Seven Alabama environmental groups petitioned the state’s Environmental Management Commission to update those standards in April, and that petition was approved at the June 13 commission meeting.

The commission, a seven-member appointed board that oversees the Alabama Department of Environmental Management, ruled in favor of the environmental groups by a 6-1 vote, despite the Department of Environmental Management’s objections.

The decision was a rare win for environmental groups operating in the deep-red state, from a board that rarely votes against the department’s recommendations.

“We’re pleased but somewhat surprised, given the historical reluctance to give environmentalists what they want,” David Ludder, an attorney representing the environmental groups, said in an interview.

Ludder said that, once finalized, the new standards will result in stricter limits on how much of these toxic substances can legally be discharged into Alabama waterways that are sources of drinking water and popular fishing areas across much of the state.

In their petition, the groups noted that the U.S. Environmental Protection Agency published new Integrated Risk Information System standards in 2015, but the state had never updated its thresholds to match. The program assesses the latest scientific research on numerous hazardous chemicals to help federal, state and local regulators determine safety standards for exposure.

“EPA did a very large reevaluation of toxic pollutants in 2015, and it was our hope that ADEM would promptly respond to that 2015 evaluation,” Ludder said. “Since then, every three years, we’ve asked ADEM to do that, to complete that evaluation, and they never were able to do it, and they never were able to provide a specific time limit for doing it.”

Ludder said commission rules require the Department of Environmental Management to use EPA-issued water standards “except where other values are established” in coordination with the Alabama Department of Public Health. That did not happen in this case.

“If you want to set aside the value of the Integrated Risk Information System, you have to develop a justification for something else,” Ludder said at the commission meeting. “And that has to be done in consultation with the Department of Public Health.”

Department of Environmental Management acting director Jeffery Kitchens told the commission the petition should be denied because it was “premature,” arguing the department needed more time to evaluate the standards, and that it was working on the water toxicity standards as a whole instead of keying in on 12 individual contaminants identified in the petition.

Kitchens said the department was moving on a timeline to propose an update to the standards by “late 2026,” aligning with the department’s policy of reviewing the guidelines every three years.

“We believe this comprehensive evaluation will result in the adoption of protective, scientifically justifiable criteria,” Kitchens said during the meeting.

Ludder countered that Kitchens’ response did not establish any firm deadlines for updating the standards and that multiple triennial reviews had taken place since 2015 without reflecting the new EPA guidance.

“The petition process is recognized by Alabama law, and it’s designed specifically to move agencies to do something, to reconsider what their rules say,” Ludder said during the meeting. “We’re asking you to do that and not defer to another triennial review.”

The commission — composed of private-sector experts in law, biology, engineering, medicine, geology and veterinary medicine, appointed by the governor — found the argument compelling.

“If our rules say we should be following (the EPA standard), we should be following it until we have a scientific basis to do something different,” Commissioner Lanier Brown, a Birmingham-based attorney, said during the meeting. “And we don’t have something different, so we’ve got to follow those.”

The commission sided with the petitioners, with only commission Chair Frank McFadden voting no.

Ludder filed the petition on behalf of seven Alabama environmental groups: the Alabama Rivers Alliance, Black Warrior Riverkeeper, Cahaba Riverkeeper, Choctawhatchee Riverkeeper, Coosa Riverkeeper, Mobile Baykeeper and the Environmental Defense Alliance.

Charles Miller, policy director for the Alabama Rivers Alliance, said he was encouraged not only by the vote, but by the level of discussion among commissioners, the Department of Environmental Management and the petitioners.

“There were a lot of good questions from the commissioners,” Miller said. “I think this is an example of what happens when we put some thought into our environmental regulations, when we take them seriously.”

The Department of Environmental Management will now be required to update its standards for 12 chemical pollutants. For five of those toxicants — cyanide, 1,3-dichlorobenzene, 4,6-dinitro-2-methylphenol, ethyl benzene and toluene — the state will switch to the updated EPA standard for an oral reference dose, mirroring the EPA’s Integrated Risk Information System reference dose thresholds.

A reference dose is the amount of a toxic substance that a person can be exposed to on a daily basis that is “likely to be without an appreciable risk” of harm. The EPA uses this metric to evaluate potentially harmful chemicals that are not considered carcinogens.

For six other compounds — 1,3- dichloropropylene, 2,4-dinitrotoluene, hexachloroethane, pentachlorophenol, trichloroethylene and arsenic — the state will use the EPA’s updated cancer potency factor. The CPF estimates how much ingesting 1 mg per day of a certain chemical will increase a person’s risk of developing cancer.

For 1,2,4-trichlorobenzene, the petition requested the state shift from using the reference dose threshold to the cancer potency factor threshold.

According to the petition, the updated standards are the result of new research and analysis by the EPA showing the chemicals are harmful at lower concentrations than previously believed.

“While the toxicity values for the toxic pollutants … may have reflected the best science and scientific judgment available at the time of their adoption by the commission, new information and scientific methods have become available which demonstrate that the toxicity values for the above-mentioned priority toxic pollutants are not sufficient to protect human health,” the petition states. “The proposed amendment will revise those toxicity values to reflect the best available science and scientific judgment and protect human health.”

Ludder said he expects the department to formally propose the updated standards around December, with the new limits incorporated into permits and advisories after that.

“The toxicity value of these chemicals is not the only consideration in establishing what level of water quality will be achieved, but it will definitely improve things,” Ludder said. “It will reduce the amount of toxins in Alabama waters.”