Glyphosate, the active ingredient in the herbicide Roundup, will soon be forbidden in Fort Myers Beach, making the town the first Lee County municipality to ban the controversial weed-killer.

Elsewhere in the state, Key West and Satellite Beach passed laws prohibiting it and several cities in California have as well.

A California jury determined in March that the widely used weed killer was a substantial factor in a California man's cancer, in a lawsuit called a bellwether for hundreds of others waiting to be tried, but many government regulators deny a link between cancer and glyphosate.

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Its manufacturer rejects such a connection, saying hundreds of studies have established that the chemical is safe. Bayer, which acquired Monsanto last year, said in a statement it "(believes) firmly that the science confirms glyphosate-based herbicides do not cause cancer."

Fort Myers Beach, which also banned plastic straws last year, has been aggressively working to protect its marine resources and reduce pollution, Mayor Anita Cereceda said. “This effort has all been about water quality.”

The potential cancer link may be an issue nationally, but as far as the beach is concerned, “We are only interested in the fact that it’s very bad for the aquatic environment,” said Shannon Mapes, the town’s marine resource task force vice chair.

Carried by landscape runoff, glyphosate can percolate into the water table and wash into Estero Bay, she said, where it can kill sea grass and the aquatic plants that serve as a nursery for the foundation of the beach food chain.

“Glyphosate is broad-spectrum, meaning it’ll kill a tree – it’ll kill anything – any plant,” Mapes said.

Cereceda said she hasn’t felt any pushback against the ordinance banning it so far. The town will be working to get buy-in with public education and outreach. There are plans to send out letters to landscaping companies and put fliers in water bills, Cereceda said. “We’ll do as much of a PR push as we can."

FGCU associate professor of marine and environmental studies professor James Douglass said banning glyphosate "seems like a simple, logical choice," he said. "Given the potential health and environmental risks of glyphosate ... the need for environmental health and public safety greatly outweigh the aesthetic concerns about weed management,” he said.

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Although glyphosate is used control unwanted plants on Lee County-owned owned land, it's handled with great care by contractors and properly certified county employees, said Lee spokesman Tim Engstrom.

The News-Press reached out to Lee County's other municipalities for comment on the herbicide; only Cape Coral responded by press time. "Staff is in the process of reviewing the use of glyphosate," wrote spokeswoman Maureen Buice in an email.

The Florida Fish and Wildlife Conservation Commission paused its herbicide program earlier this year to gather public input, but has since resumed spraying. Calls and emails to agency officials were not immediately returned.

Calusa Waterkeeper John Cassani wonders whether banning something that's long been approved for use by the Environmental Protection Agency could create future legal challenges.

“Glyphosate has an EPA label,” Cassani said. “I just wonder about banning a substance that’s legal to use,” he said. “I’m not saying it’s good or right or just, I’m just saying (that) I don’t know how you can prevent people from using it if it has a federal label.”

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Cereceda contends that her town must take a stand. "We can’t be hypocritical about this," she said. "We can’t constantly be pointing our fingers at Lake Okeechobee and the farmers and everybody else when we ourselves aren’t doing all we can to monitor and eliminate what we can here in the island. So this was the next thing on our hit list."

Improving water quality will be an ongoing effort, she said. "Little by little, we try to make an impact, and so far, so good."