Rejecting pleas for delay, the Palm Beach County Commission on Tuesday declared again its intention to fluoridate the county water system.

But the issue will receive another airing before the fluoride switch is flipped on.

The 5-2 vote means the Water Utilities Department will seek bids within a month on a range of improvements to its plants, including an estimated $600,000 of work to fluoridate the water for 425,000 residents.

Utilities Director Gary Dernlan said fluoridation could begin in November.

That’s the same time a National Research Council study of fluoride is due for completion, and commissioners said they wanted to learn the results before the substance is added.

If the study is late, County Administrator Bob Weisman said he would ask commissioners if they want to proceed.

Fluoride opponents wanted to delay the construction work until after the federal report.

Patricia Moreell, an anti-fluoride activist in Boca Raton, said fluoride causes a range of problems including bone cancer and birth defects.

Naomi Flack of Palm Beach Gardens, representing South Florida Citizens for Safe Drinking Water, asked commissioners to pause “before putting this industrial waste product into Palm Beach County drinking water.”

But Dr. Jean Malecki, director of the county Department of Health, urged commissioners to move forward. She said decades of study have proved fluoride is safe and effective.

Everyone benefits from fluoridation, even though it is especially important for children, Malecki said. When children have good teeth, they eat well and perform better in school, which is an important benefit to society, she said.

The county water system’s primary territory is west of Boca Raton, Delray Beach and Boynton Beach. Homeowners associations representing many of those residents favor fluoridation.

Larry Zalkin, representing the Alliance of Delray Residential Associations, said the county should “proceed as rapidly as possible.”

Delay would “give the impression that we, the residents of Palm Beach County, have little concern” over children’s health, he said.

Commissioner Jeff Koons, Burt Aaronson, Addie Greene, Karen Marcus and Warren Newell voted to proceed.

Commissioners Tony Masilotti and Mary McCarty voted against going ahead.