Fluoridated toothpaste was invented in Bloomington, but until recently, the city drinking water supply lacked the mineral.
Bloomington experienced almost five years of inconsistent fluoridation from Bloomington’s water supply, which comes from the Monroe Water Treatment Plant. But on Jan. 28, the city reintroduced fluoride into the system.
Citing a reoccurring leak in the fluoride bulk chemical storage tank that started in 2019, city utilities completely discontinued fluoride service in 2023 due to upkeep costs and safety hazards to water plant workers, the B-Square Bulletin reported in summer last year.
According to the Centers for Disease Control and Prevention, fluoride in water reduces tooth decay by about 25% in children and adults. Additionally, a 2016 study found that communities with fluoridated water save $32.19 per capita on cavity treatments.
Fluoride is a naturally occurring mineral in water supply. Bloomington began supplementing the water in 1967, raising the amount of fluoride to CDC approved levels to help prevent tooth decays.
The city’s new temporary water system uses multiple smaller tanks instead of a bulk storage tank to hold the chemical. According to a Monday press release, the city hopes the new system will reduce safety risks for staff, lower operational costs and make future replacement efforts easier.
“This solution meaningfully addresses a community concern while strengthening the overall reliability of the fluoride delivery system,” Bloomington’s Utilities Director Katherine Zaiger said in the release. “I appreciate the time, expertise, and problem-solving our staff brought to this project.”
According to information the CBU provided the B-Square Bulletin, fluoride levels in Bloomington have averaged below 0.25 milligrams per liter since April 2021. The CDC recommends that levels are 0.7 milligrams per liter.
City of Bloomington Utilities failed to report lack of fluoridation to residents according to the B-Square Bulletin. The problem first went public following personal research from IU Associate Scientist Katherine Edmonds.
Edmonds found fluoride levels were 0.09 milligrams per liter in a footnote in the 2025 Bloomington Annual Drinking Water Quality Report.
“These kids right now, like my kids age, who missed out on ingesting fluoride for a couple of years, those were critical years where their adult teeth are developing,” Edmonds said. “I feel like my children have been significantly harmed by this.”
In the Feb. 9 press release, the city addressed its lack of transparency when fluoride was initially discontinued, saying it “acknowledges that public reporting on fluoride levels was inconsistent in prior years.”
As of July 2025, the city requires the CBU to present the consumer confidence report in a public meeting of the Utilities Service Board annually, the press release said. Utilities Service Board meetings are twice a month on Mondays from 5-7 p.m at the city Utilities Service Center. The meeting schedule can be accessed on the city website.
Indiana is ranked 12th in fluoridated water systems across the country with 91.5% of the population using community water services received fluoridated water, according to a 2022 report from the CDC.
Though considered by the CDC to be one of the greatest public health achievements of the past century, concerns about fluoridating water systems have arisen in recent years. According a report by PBS, Utah banned the practice in March 2025, and Secretary of Health Robert Kennedy Jr. campaigned for the CDC to stop endorsing fluoridation.
Opponents to fluoridation are concerned that a mix of fluoridated water and toothpaste will lead to overdosage. Large amounts of fluoride can cause children under eight to develop fluorosis, a condition causing white flecks on the teeth according to the CDC. A 2025 study by the Journal of American Medical Association linked 2 milligrams per liter or greater fluoride exposure to lower IQs.
However, these effects have not been found when fluoride levels meet the CDC regulated amount of 0.7 milligrams per liter.
Bloomington’s new temporary system will be incorporated into a permanent fluoridation system as part of the CBU’s Capital Improvement Program, which has several long-term projects to improve the water treatment plant including creating an improved cybersecurity system and rebuilding high service pumps.
The permanent system will be created by “replacing and restoring any equipment or surrounding infrastructure” that wasn’t fixed through the temporary repairs, Daniel Frank, CBU communications manager, said in an email.
