A Mississauga woman says she's re-opening a dormant lawsuit she launched against Peel Region over the fluoride it adds to tap water to prevent tooth decay.

Liesa Cianchino sued the region three years ago, alleging that by fluoridating drinking water, the region is medicating the public without permission.

That violates the Charter of Rights and Freedoms, her suit says, as well as the province's Safe Drinking Water Act.

"We believe we are being mass medicated without our consent," Cianchino told CBC Toronto Wednesday. "Injested fluoride is definitely harmful for the young, for the sick, for the well, for the old ... We want [a court] to rule that water fluoridation is illegal."

Although she cites several academic studies and books to make her case, her assessment is disputed by Dr. Jessica Hopkins, Peel's medical officer of health.

Peel Medical Officer of Health Dr. Jessica Hopkins says the region's drinking water is safe. (Mehrdad Nazarahari/CBC News)

"Community water fluoridation is not dangerous. In fact, it's safe," Hopkins told CBC Toronto Wednesday. "We have 70 years of data that this is safe and it works to prevent cavities."

Cianchino's lawsuit is scheduled to be raised at a meeting Thursday of Peel Regional Council.

Coun. John Sprovieri, who backs Cianchino's claims, has put forward a resolution calling on council to bring in outside legal experts to determine whether she has a case.

If she does, he says, the region should end its defence of the suit and voluntarily stop fluoridating drinking water.

Peel Coun. John Sprovieri's resolution on the safety of the region's fluoridated water will be discussed Thursday. (Mehrdad Nazarahari/CBC News)

But that would be a mistake, according to other councillors.

Councillors Carolyn Parrish and Ron Starr both say they're satisfied with a move the region made earlier this year to slightly reduce the concentration and amount of fluoride in the water.

"We've made the decision to keep the fluoride in the water at this point," Starr said Wednesday." At this point it looks the fluoride is satisfactory to all of us on council."

Liesa Cianchino has been campaigning against the use of fluoride in municipal water supplies for several years. (Mehrdad Nazarahari/CBC News)

Cianchino and Sprovieri both maintain that fluoride can aggravate existing medical conditions and lead to decreased IQ levels in children.

"The studies have shown that it reduces the intelligence of children that have been exposed to higher levels of fluoride," Sprovieri said Wednesday.

But Hopkins disputes that notion: "We have not found any adverse health effects beyond dental fluorosis which is a cosmetic whitening that can occur on the teeth and in most cases you'd need an experienced dental professional to see those changes."

Peel Coun. Ron Starr says he's confident Peel's fluoridated water is safe. (Mehrdad Nazarahari/CBC News)

Shortly after Cianchino launched her lawsuit in 2014, the region formed a special committee to look into the issue.

That was enough to convince Cianchino to suspend her court action, she said Wednesday.

The committee issued a report in February asking the province to make a ruling on the wisdom of fluoridating water. But so far, there has been no reply, according to Sprovieri.

Resolution before council Thursday

Now, his resolution to council states he wants council to hire a lawyer who can provide "an opinion on the assertions of illegality and unconstitutionality raised in the Cianchino Action ... and recommend any steps that council or councillors should be taking to fulfill the "post-Walkerton" statutory standard of care in respect providing safe drinking water."

Cianchino says she's decided to restart her lawsuit out of frustration with the delays.

'Outrageous'

"We're into the eighth month," she said. "This is outrageous."

Ciachino said Wednesday her lawsuit does not seek a monetary penalty; she's only asking that the court order Peel to remove fluoride from tap water.

Several Canadian communities have taken that step voluntarily, including Windsor, Ont., which removed fluoride from its drinking water back in 2013.

At least one Windsor dentist has said she's seen an increase in tooth decay in children since fluoride was removed.