An IU [Indiana University] School of Dentistry professor played a leading role in developing the “gold standard” for analyzing fluoride and also chaired a panel of experts that helped set new government recommendations for the amount of fluoride to be put in drinking water in the United States to prevent tooth decay.
Dr. E. Angeles Martinez-Mier served as the primary investigator of a large research team that was funded by the National Institutes of Health to develop simple global gold standard measurements to enable researchers to more accurately, rapidly and conveniently analyze and monitor fluoride levels. The team was composed of 19 researchers in nine laboratories located in seven countries on four continents.
She also played a role in developing new government guidelines on fluoride in drinking water, chairing a panel of experts that reviewed the U.S. Environmental Protection Agency’s 2010 fluoride risk assessment and sources of fluoride.
Fluoride has become a potent weapon against tooth decay in the U.S. since it was added to drinking water beginning in the 1940s. “It is considered one of the top 10 public health achievements of the last century,” Martinez-Mier said.
Because it is used widely and impacts public health, researchers have conducted numerous studies of fluoride. But testing techniques have varied, producing slightly different results even when researchers are conducting the same tests on the same kinds of samples.
“When you are dealing with public health issues you want to compare test results and generalize from those test results,” Martinez-Mier said. Different testing methods that produced different results made that difficult to do.
Further, a lot of basic research on fluoride was done before some of the techniques now in use were developed, she noted. “There is a need to constantly monitor.”
Led by Martinez-Mier, the research effort to develop gold standards for testing fluoride included many of the leading names in the field, including Dr. Domenick Zero, the IU dental school’s associate dean for research and Oral Health Research Institute director, and Zero’s predecessor at IU, Dr. George Stookey.
Working with labs that had published the most about fluoride in the last decade or so, Martinez-Mier and the other researchers began comparing in minute detail each step of various testing techniques that were in use to analyze fluoride to come up with gold standards.
The gold standards that were developed are a series of standardized steps that go from the equipment to be used to the preparation of a sample, to analysis, to reporting, she said.
“It involved a lot of negotiations initially, because researchers are passionate about the methods they use and believe are the best,” Martinez-Mier said. “But in the end numbers talk.”
An article by Martinez-Mier about the gold standards was published last winter by “Caries Research,” an international journal considered the world’s top publication in the field of dental caries, or tooth decay.
The federal government announced in January that its new recommendations for the maximum amount of fluoride to be placed in drinking water called for 0.7 milligrams of fluoride per liter of water, replacing what had been the standard of 0.7 to 1.2 milligrams. Martinez-Mier’s role of chairman of a panel of experts reviewing what the standard should be had an impact on the final level agreed upon.
When the previous standard had been set some 40 years ago, the use of fluoride was not as widespread as it is today, she said, noting that fluoride is used in a number of products now, from toothpaste and mouth rinses to medicine for such common conditions as high blood pressure.
Widespread use of cooling systems helped eliminate the need to have a range on the fluoride recommendations. Until air conditioning became commonplace in the U.S., water consumption in the north and the south varied due to the weather
“We know fluoride is the best weapon we have against caries, and we know it is extremely effective,” she said. “At the same time, we want to be very careful in how much is used. Most substances have the potential to be toxic — even water, if you drink too much of it. We want to make sure we have it right.”