Beginning in the 1980s, Elgin, like many Texas towns, put fluoride in its water. But in 2005, with the construction of a new water treatment plant interfering with operations at its facilities, the city’s water utility decided to temporarily suspend its fluoridation.

The treatment plant is now complete, but Elgin’s City Council is considering making the suspension of fluoridation permanent.

The issue, which has led to debate about the makeup of drinking water, could go to Elgin’s voters next May.

The debate flames up now and then about the efficacy of a fluoride compound that became popular in the 1940s.

In recent years, cities as large as San Antonio have wrestled with whether to fluoridate drinking supplies. Austin has fluoridated its water since 1972, when the public decided to do so in a city referendum by a margin of 16,964 for and 12,687 against.

Fluoride has been credited with preventing tooth decay, and its use is strongly encouraged by the American Dental Association.

“Community water fluoridation remains one of the great achievements of public health in the twentieth century,” the surgeon general’s office said in the 2000 report “Oral Health in America.”

But the fluoride compound Elgin is considering adding to its drinking water, called hydrofluosilicic acid, can contain trace amounts of heavy metals, including lead, and some critics have pointed to research that shows that rats exposed to high levels of fluoride develop cancer. The Sierra Club does not endorse fluoridation, and the head of Elgin’s public water utility says he is against fluoridating the water. Opponents also say the government should not mandate medication.

“I’m supposed to get as much lead out of the water as possible,” Doug Prinz, the director of utilities for Elgin, ,said. “Why am I putting a chemical in it that contains it?”

Texas, like most states, leaves it up to water suppliers to decide whether to fluoridate their water, but the Department of State Health Services recommends fluoridation.

Scientists and dentists have said fluoride can be beneficial in low concentrations. Fluoride strengthens a tooth’s fortifications against tooth decay, said Carl Herring, an Elgin dentist who has pushed for fluoridation.

The Texas Commission on Environmental Quality has taken a neutral position on fluoride, though it does enforce a maximum level to prevent overexposure.

Evidence regarding fluoride’s potential in drinking water to cause cancer, particularly of the bone, is tentative and mixed, a 2006 report by the National Academy of Sciences found.

Adding fluoride to Elgin’s water would cost at least $14,000 a year, said Prinz, who said individuals can fluoridate their own water by using fluoride tablets or buying bottled water that already contains fluoride. The dental association says that generally, every dollar invested in community water fluoridation saves $38 in dental treatment costs.

But the argument has gone beyond dollars and cents.

“It’s my job to protect my family,” said Sue Brashar, a 38 year-old who lives in Elgin with her husband and 19-year-old daughter and asked the City Council not to resume fluoridation at a hearing earlier this month. “If I see something that might hurt them, I’ll speak up, and so I did on fluoride.”

At its meeting Nov. 20, the City Council could decide to fluoridate the water, not fluoridate it, or let voters decide.

Here and there, communities in Central Texas can be found that do not fluoridate their water, including Smithville, Giddings, Manor, Woodcreek, Hutto, Taylor and Johnson City, according to 2006 records from the Centers for Disease Control and Prevention.

Even so, more Texans are getting fluoridated water than ever before: Nearly 78 percent on public water systems currently receive fluoridated water, according to the Department of State Health Services.