The MWRA provides wholesale water and sewer services to 2.5 million people and more than 5,500 large industrial users in 61 metropolitan Boston communities. The MWRA has fluoridated its drinking water since the 1980s, maintaining a target fluoride level of 1.0 parts per million.

MALDEN – The Massachusetts Water Resources Authority is lowering the amount of fluoride added to the water it supplies in accordance with a new recommendation from the Centers for Disease Control.

The MWRA announced the change in a press release sent out on April 29.

On April 27, the CDC released a recommendation that water suppliers reduce their fluoride dosage to 0.7 milligrams per liter from a range between 0.7 mg/l and 1.2 mg/l.

According to the CDC, the dose is being lowered because Americans now receive fluoride from a variety of sources, other than just water, and the dental benefits can be achieved with a lower dose in water.

“MWRA has been adding fluoride to the water for more than 30 years to reduce tooth decay and promote community public health,” said Fred Laskey, the MWRA’s executive director, in the release.

“Like most other water suppliers, we follow the recommendations of the CDC, as well as the World Health Organization and the American Dental Association,” he added. “These are the public health experts, and we look to them for guidance on this important issue.”

MWRA has adopted the new recommendation at its Carroll Water Treatment Plant, which serves 45 communities in eastern and metro west Massachusetts, including Greater Boston.

Benefits of flouride [sic]

According to the DPH Office of Oral Health, the benefits of water fluoridation are clear. They include “fewer and less severe cavities, decreased need for fillings and tooth extractions, and reduced pain associated with tooth decay.”

The MWRA cites a CDC report, “Ten Great Public Health Achievements — United States 1900-1999,” that pinpoints fluoridation of public water to reduce tooth decay as one of the leading public health achievements of the last century.

According to the CDC, 4.7 million residents across the commonwealth receive fluoridated water. That is 70.4 percent of all residents on community water systems. This includes Malden, which is an MWRA community. Malden began putting fluoride in its water in 1978, according to the state Department of Public Health.

The CDC calls water fluoridation the least expensive way to deliver the benefits of fluoride to all residents of a given community. It estimates that for larger communities of 20,000 or more, it costs about 50 cents per person to fluoridate the water and that every $1 invested in the preventative measure translates to about $38 in savings in dental treatment costs.

But there has been a push to lower fluoride levels in drinking water, and the change was anticipated.

In February, Ria Convery, of the Massachusetts Water Resource Authority, said the EPA, which sets fluoride standards to guard drinking water safety, was looking at the reduction the MWRA is now adopting.

“I should note that the EPA is currently evaluating [changing] the recommended dosage from 1.0 parts per million to 0.7,” Convery said in February. “When and if that change occurs we will lower our target as well.”

Concerns about flouride [sic]

There has also been a push to discontinue the use of fluoride in drinking water.

Communities in the United States have been fluoridating water systems since the mid-1940s, and fluoridation became an official policy of the U.S. Public Health Service by 1951. By 2006, nearly 70 percent of the country’s population serviced by public water systems (and nearly 62 percent overall) were receiving fluoridated water.

“When this started in 1945, the belief was you had to swallow fluoride so the teeth below the gums wouldn’t decay,” said Carol Kopf, of the Fluoride Action Network, or FAN. “They thought fluoride was a magic bullet.”

FAN’s mission is to “broaden awareness about the toxicity of fluoride compounds among citizens, scientists, and policymakers alike.” Kopf and many others in Massachusetts and across the country now believe that, not only is fluoride not the answer to perfect teeth, it’s harmful in other ways.

Another concern is the risk of dental fluorosis, which leaves white, almost lacy markings on tooth enamel. Kopf, who has been fighting mandated water fluoridation since the 1980s, said it comes from over-fluoridation and estimates that 40 percent of American teenagers have those markings.

The DPH instead calls fluoride a natural occurring mineral that when added to water can prevent tooth decay by as much as 60 percent in baby teeth, and by as much as 35 percent in adult or permanent teeth.

Kopf also argues researchers have since discovered fluoride is only truly effective when used topically, not by drinking. Reports from the CDC counter that notion, stating, “even today, with other available sources of fluoride, studies show that water fluoridation reduces tooth decay by about 25 percent over a person’s lifetime.”