A Harvard study published in the Journal of the American Medical Association found that mercury-containing tooth fillings—known as amalgams—do not have adverse affects on a child’s neuropsychological and kidney functions.

The study, published Wednesday, was met with criticism as physicians at other institutions decried the “outrageous human experiment on indigent and orphaned children,” according to a press release from the International Academy of Oral Medicine and Toxicology (IAOMT).

“What they did is flat out wrong. Harvard is high quality. This is a mistake that’s going to hurt them,” said IAOMT member Boyd E. Haley, a professor of bio-organic chemistry at the University of Kentucky and a leading critic of the study. The IAOMT promotes mercury-free dentistry.

Haley alleges that the parents of the children participating in the study were not well-informed about the amount of mercury their children would be exposed to.

But Harvard Medical School Professor of Neurology David C. Bellinger, lead author of the study, says, “All I can say is based on the way amalgam was used in this study in the amounts it was given over the five years following, we did not see any increased health problems.”

Half of the children received mercury amalgam fillings which are approximately 50 percent mercury. The other half of the group received white composite resin fillings, containing no mercury, according to the study.

According to Bellinger, mercury fillings are more durable and less costly than composite fillings. He said that the controversy surrounding mercury fillings has overshadowed the fact that little research has been done on the long-term health effects of composite fillings.

The IAOMT filed complaints against Harvard, the University of Washington, the University of Maine, and other sponsors of the study on Tuesday with each of the respective institutional review boards.

Bellinger, however, defended the study’s methods and said that telling the parents about the experimental method would not have contributed to the quality of the study.

“These things are always complicated,” he said. “So, we could have told the parents how many micrograms [of mercury] were in the filling, but how do you interpret that for them?”

A consent form signed by the parents of the children explained that an exposure to mercury can cause a number of side effects ranging from dizziness to headaches.

Haley alleges that the authors of the study do not want to admit to the harmful side effects of mercury because of financial motives.

“The average dentist can place three amalgam fillings by the time they place one composite filling,” said Haley. “It’s absolutely a money thing and saving face.”

Haley said that Harvard should expect lawsuits to be brought forth by parents of the children who participated in the study. “I don’t see how they’ll escape it,” he said.

The study was conducted from 2000 to 2005 on 534 children, aged 6 to 10. Half of the participants were from Boston and the other half were from Farmington, Maine. The participants received free dental care, and incentives such as free gift certificates for CDs for each completed dentist visit.

The study made no claims about the long-term effects of exposure to mercury, according to Bellinger. “There is a possibility that some subtle effects might emerge years from now, but based on what we’ve seen so far, I don’t know what the likelihood of that is,” he said.