Portland Again Rejects Fluoride in Bitter Vote Stays biggest city in US without fluoridation By Rob Quinn, Newser Staff Posted May 22, 2013 4:52 AM CDT 59 comments Comments Signed petitions against fluoride are turned in at Portland's City Hall. (AP Photo/Don Ryan) (Newser) – The good voters of Portland, Ore., have once again rejected plans to add fluoride to their water to combat tooth decay, keeping it the biggest American city without fluoridation. The city voted 60% to 40% to stay fluoride-free last night, the fourth such rejection since 1956, the Oregonian reports. Fluoridation passed a vote in 1978, but the decision was overturned two years later before any fluoride was added to the water, the AP reports. More than $1 million was spent during a bad-tempered campaign that saw both sides accusing the other of sign-stealing and using junk science. Opponents of fluoridation argued that its effects on the body might not be fully understood. "I don't want chemicals in my water," one woman said after voting. "I know that there are really no known health risks with it, but there's a lot of things we find out later in life really do have health risks."