TALLAHASSEE — A state panel will decide today whether to allow polluters to increase the level of toxic chemicals they dump into Florida rivers and lakes as part of the first update of the state's water quality standards in 24 years.

The governor-appointed Environmental Regulatory Commission will vote on a rule proposed by state regulators that would increase the number of regulated chemicals allowed in drinking water from 54 to 92 chemicals and raise the allowed limits on more than two dozen known carcinogens — all currently regulated — from levels that are from 20 percent to 1,100 percent higher than current standards. The agency is reducing the allowed limits on 13 currently regulated chemicals, two of which are considered carcinogens.

The dozens of chemicals are among those released by oil and gas drilling companies (including fracking operations), dry cleaning companies, pulp and paper producers, wastewater treatment plants and agriculture. Many of these industries have come out in support of the new rule.

For environmentalists, the proposal is an unacceptable no-brainer.

"Toxic algae blooms in South Florida are making people sick, hurting our economy, closing our beaches, and the Rick Scott administration wants to legalize even more toxic chemicals in our water?" said Linda Young, director of the Florida Clean Water Action Network, which is fighting the rule. "It's so crazy it seems unreal, and they're not even embarrassed by it."

For the Florida Department of Environmental Protection, which proposed the rule using its own new model for determining cancer risk, the measure is a long-overdue update required under the federal Clean Water Act. The agency last updated the list of regulated toxic chemicals in 1992 and began working on the new proposal in 2012, after years of review, said Dee Ann Miller, a DEP spokesperson.

The draft rule incorporates new methods for understanding the amount of toxins that pose a human health hazard, Miller said. In addition to revising the standards on dozens of chemicals currently regulated, it will impose new regulations on 39 chemicals that the agency currently does not limit.

"DEP's and EPA's nationally recognized scientists have worked diligently for multiple years to develop the criteria, which incorporate both the EPA guidance and data specific to Florida," Miller said. "The criteria take into account how, and how much, Floridians eat seafood, drink, shower and swim, and set the limits necessary to protect us all from adverse health effects."

Among the chemicals on which DEP would impose new limits are cyanide and beryllium. The criteria also imposes stricter limits on a handful of current chemicals, such as the chlorinated solvent called trichloroethylene, or "trike", a compound known to cause birth defects and cancer. The proposal would drop the allowed level in drinking water, from 2.7 to 1.3 parts per million.

Environmentalists say that most of the new criteria would weaken current guidelines, allow for toxin levels higher than the federal standard, impose no regulations on dioxins and expose Floridians to higher cancer risk.

For example, benzene, a known carcinogen that environmentalists say is found in the wastewater of oil and gas fracking operations, would go from 1.18 parts per billion in Florida's drinking water to 2 parts per billion under the new criteria. The federal standard is 1.14 parts per billion.

DEP has told lawmakers in the past that it does not have the authority to reject a fracking permit if one was requested. Miller said "there is no active drilling" and the department has not received any current notices that fracking is occurring.

The agency said it developed the new "probabilistic analysis" to be more Florida-specific, shielding people who consume large amounts of fish from the buildup of dangerous toxins. It says the new rule is stricter than the federal standards and was reviewed by "scientists at EPA, Florida Department of Health, four Florida universities and the California Environmental Protection Agency."

But environmentalists warn that no other state uses Florida's "probabilistic analysis" method for detecting cancer risk — for a reason. They argue that the assumptions in the state rule underestimate the amount of seafood Floridians eat and, because toxins that accumulate in fish or shellfish are passed along to humans who consume them, the cancer exposure will increase for people who eat Florida-caught seafood more than once per week.

For example, the environmentalists argue, where EPA standards allow for toxin levels that could cause cancer in 1 in a million people, the toxin levels allowed under the Florida methods increase the number of cancer victims to 1 in 100,000 people, or, in cases of people who eat fish daily, 1 in 10,000.

DEP's new cancer-risk measurement is supported by the pulp and paper industry, which sees it as "more scientifically advanced as it addresses compounded conservatism, links risk targets with environmental concentrations, improves transparency and makes greater use of available data," Jerry Schwartz of the American Forest and Paper Association wrote in a letter to DEP last month.

But a petition signed by more than 2,700 people from across the state disagrees. The petition urged the agency to reject the rule and "to protect public health and the environment, not the wallets of the big polluters."

DEP Secretary Jon Steverson defended the proposals in a statement released late Monday.

"I've been in contact with the federal EPA, which has confirmed every change is in line with its own recommendations,'' he said.

DEP moved up the vote on the proposed rule from September to today without offering a reason. The Environmental Regulation Commission hasn't met since December and two of the seven positions — the representative for the environmental community and another representing local government — have been left vacant by Gov. Rick Scott.

Former Gov. Bob Graham and the Florida Conservation Coalition, which represents more than 50 Florida environmental groups, wrote Scott on June 16 asking him to fill the posts but they never received a response. Democrats in Florida's congressional delegation sent a letter Monday urging the commission to reject the new rules, saying they were an environmental and public health threat.

Last week, several Miami-Dade County elected officials sent a letter to Steverson urging the agency to postpone the vote and seek more public comment. They argue rules "would result in increased concentrations of toxic chemicals in our waterways, threatening our water quality, public health and water-based economies upon which millions of Floridians depend."

Tampa Bay Water warned of the weak structure the agency is using to enforce the rule, saying it was "relying on water utilities (some with very little resources) to identify threats from 'discharged substances.' "

And Bud Nocera of the Fort Myers Beach Chamber of Commerce wrote that the rule did not "protect our island's tourism industry and the livelihood of our members by protecting our waters from toxic chemicals."

Meanwhile, many in the environmental community have concluded that the new rules, and the agency's decision to fast-track a vote today, are evidence that DEP may be laying the groundwork to bring fracking to Florida, Young said.

Several of the chemicals that will be allowed to be increased in Florida waters are related to benzene and are thought to be used in fracking, she said. The Florida Legislature has three times tried and failed to pass legislation to prevent local governments from banning fracking and to shield the fracking chemicals used by the industry from public record. DEP has supported the legislation.

"The benzene thing is strictly for the oil and gas industry — for fracking," Young said. "There is no other explanation."

The department denies the rule is being fast-tracked to pave the way for fracking in Florida.

"This rule update stems from requirements under the Clean Water Act as well as the new EPA guidance," Miller said. "It is not in response to any specific industry or practice and has nothing to do with hydraulic fracturing."

Contact Mary Ellen Klas at meklas@MiamiHerald.com. Follow @MaryEllenKlas.