Two environmental groups have announced their opposition to Portland's plan to fluoridate the city water supply. Both the Sierra Club and Columbia Riverkeeper say the health benefits don't outweigh environmental risks.
Portland voters will decide in May whether the city should go forward with its fluoridation plan.
"The Sierra Club's position is, we don't need more chemicals in our water," said Antonia Giedwoyn, a Sierra Club spokeswoman. "We should be working to reduce the number of chemicals in our water."
Giedwoyn acknowledged Portland already adds products like chlorine and ammonia to the city's water, but she said her group does not take a position on chemicals added for potability.
She points to a 1989 study near the John Day Dam. It found fluoride released in the Columbia hindered the survival of wild salmon.
Fluoride supporters argue that study didn't explore much lower levels of fluoridation.
Mel Rader with Upstream Public Health, a group that supports fluoridation, said adding fluoride at the recommended level would have no measurable effect on the Columbia River.
Another regional group, Willamette Riverkeeper chose not to take a position, given the available research.
The report originally appeared at OPB News.