WATSONVILLE — Watsonville is joining a growing list of California cities that have banned popular glyphosate weed-killers from use on public land amid mounting concerns of public health effects.

Watsonville banned the herbicide from use on city-owned land in a unanimous City Council vote on April 23. The ban takes effect July 1, with an exemption granted to the Watsonville Municipal Airport until runway renovations are completed at the end of the summer.

Glyphosate, the active ingredient in the Monsanto-developed herbicide Roundup, is the most popular weed-killer in the U.S., according to a 2016 study. Concerns that the chemical could cause cancer have mounted in recent years, but evidence remains mixed.

The World Health Organization classified the weed-killer as a likely carcinogen in 2015, and California became the first state to list glyphosate as a known carcinogen in 2017. On Tuesday, however, the Environmental Protection Agency reaffirmed its stance that glyphosate poses no known health risks when used as directed, and is likely not carcinogenic.

Meanwhile, Roundup-maker Bayer — which acquired Monsanto last year — faces hundreds of ongoing lawsuits over the herbicide. In March, a California man who claimed Roundup caused his cancer was awarded $80 million in damages by a San Francisco jury. Last year, another cancer patient was ultimately awarded $79 million in a similar case.

Bayer has insisted Roundup is noncarinogenic and safe when used as directed.

Use of glyphosate on public land is already banned or heavily restricted in dozens of California cities, counties and school districts, including the nearby cities of Santa Cruz and Greenfield and the Pajaro Valley Unified School District. Los Angeles County became the largest local government to enter the fray in March, issuing a moratorium on the weed-killer and citing the need for more research into its potential harm.

Watsonville city staff had recommended a more cautious approach, calling for the city to implement an Integrated Pest Management plan and suspend the use of glyphosate use at popular parks while studying the issue over the next year.

Banning glyphosate outright, according to Watsonville’s parks director Nick Calubaquib, is likely to lead to reduced maintenance of parks and medians unless more funding can be found for pricier, less effective alternative herbicides and manual weed-removal.

Allowing more weeds to grow can lead to different risks and health impacts, such as fire outbreak, ticks and allergies. However, to what extent the ban will impact Watsonville’s weeding and maintenance remains unknown, according to Calubaquib.

Watsonville Mayor Francisco Estrada acknowledged the City Council’s decision could complicate maintenance, but said he felt it was a necessary step to put public health concerns first.

“I think that this was something that was within our reach and something I could participate in to make a positive change,” Estrada said in a recent interview.

“Will there be a cost, yes, will there be consequences, yes,” he said. “I’m ready for the consequences. If weeds start growing out everywhere, I invite the public to send me an email and I’ll be happy to explain the rationale behind my decision.”

Living in a city surrounded by farmland, exposure to pesticides and herbicides is of particular concern to many Watsonville residents. Dozens of teachers, parents, and other concerned community members continue to advocate to reduce students’ exposure to pesticides in Santa Cruz and Monterey County, organizing as the Salinas-based coalition Safe Ag Safe Schools.

Safe Ag Safe Schools community organizer Sarait Martinez applauded Watsonville’s glyphosate ban as a step in the right direction.

“We have cities that are surrounded by fields and kids are already being exposed in schools to this pesticide drift,” Martinez said. “It is concerning. If we can do something to limit this exposure in cities by taking this step, it is great.”

Watsonville’s ban was also lauded by Mark Weller, co-director of Californians for Pesticide Reform.

“Monsanto has been hiding their cancer research for decades, putting their company profits over human health,” Weller said. “Now that the science is in the open, it’s heartening to see cities like Watsonville taking the lead in protecting their residents by banning glyphosate.”