by KRISTIAN GRAVENOR

Inside a small water treatment plant in Dorval sits a red metal box beneath a giant funnel that feeds white powder into the water supply, sending it down a pipe and eventually to nearby homes. "The equipment's very old. They've got to decide if they want to get a new one," says an official. "They have to make a decision right away."

The antiquated apparatus that drops fluoride powder into the West Island's water system is a rare beast, for not only do virtually all such systems now use liquid forms, but it's one of only a handful in Quebec that add the tooth-hardening substance to the water supply. Two of the seven island water plants put fluoride into the water for the benefit of a tiny, well-off minority of citizens living in Pointe Claire, Dorval, Beaconsfield, Baie D'Urfé, Kirkland and parts of Dollard des Ormeaux and Ste. Anne de Bellevue.

According Alan DeSousa, the city councillor responsible for water, any decision on the future of fluoridation is still yet to be discussed. But dentists and public health officials consider it an urgent mission to get it in the water.

"I'm certainly in favour of fluoridation," says Dr. Marcel Tenenbaum, a dental public-health consultant for the Montreal Public Health Department. "Health Canada, the provincial Minister of Health, the Regional Health Board, the Center for Disease Control, National Institute of Health and the World Health Organization are all in favour of it, so I'm going along with the big boys," he says.

Only eight per cent of Quebec's residents get fluoridated water in their pipes, including those of Quebec City, Trois Rivières and Sherbrooke - versus about two-thirds of Ontarians.

"Quebec children have twice as many cavities as children in Ontario," Tenenbaum says. "It only costs about $1 per year per person to prevent fillings that cost about $80 to repair. And once you've had a filling, then eventually the fillings have to be changed and more of the tooth structure is destroyed," he says.

Tenenbaum suggests that it's unethical to allow the poorer citizens to go without fluoridation. "Few people will go through the trouble of putting drops in their kids' water every day for 12 years. It's middle-class behaviour, the poor and single parent families don't have the money for us to ask them to spend $100 a year on fluoride drops for their kids. Fluoridating the water supply is the ideal public health intervention - it's amazingly cheap, it benefits all and the population doesn't have to do anything."

Montreal remains the last city with a population over one million in the U.S. and Canada that doesn't fluoridate its water. The last time it was proposed, in the Doré era, a small committee of opponents cited questions about the safety of the practice and the initiative was abandoned.

But exhaustive studies and the lack of a major health crisis related to the practice in places that have fluoridated their water for almost 40 years have caused the anti-fluoridation movement to lose some credibility.