Infants fed formula mixed with fluoridated water could ingest more than the recommended amount of the tooth-toughening substance, which could lead to spotted or discolored teeth, a state health official said this week.

Spokesman Gregory P. Moore said the state Department of Health and Human Services is asking two federal agencies — the FDA and the Centers for Disease Control and Prevention — for guidance on the matter. The request follows a statement in November from the American Dental Association, which raised concerns about infants fed formula reconstituted with fluoridated water.

“At this point, from our perspective we think it’s important for the public to realize there is a potential for fluorosis with the continual use of fluoridated tap water in reconstituted baby formula,” Moore said.

Fluorosis occurs when teeth that are under formation become exposed to too much fluoride. The result can range from barely noticeable white spots on the teeth to pitting and staining.

Public water in Manchester and surrounding towns has been fluoridated since late 2000. Other fluoridated public water systems in New Hampshire include Concord, Dover, Hanover, Laconia, Lancaster, Lebanon, Portsmouth and Rochester.

Moore said health officials are receiving mixed signals about fluoride and infants since the ADA released its guideline.

The federal Womens, Infant and Children program, which provides formula and other products to mothers and children, has not changed its recommendation. WIC encourages mothers to mix formula with fluoridated water, Moore said.

The ADA said it acted after the National Research Council raised the possibility of higher-than-optimal levels of fluoride for infants who drink formula.

“While more research is needed before definitive recommendations can be made on fluoride intake by bottle-fed infants, the American Dental Association issues this interim guidance because we know that parents and other caregivers are understandably cautious about what is best for their children,” the ADA writes in its statement.

And last month, the Vermont Health Department recommended that formula be mixed with non-fluoridated or low levels of formula. State health officials stressed that occasional consumption of fluoridated water by infants will not harm developing teeth.

“At this point we are seeking additional guidance on the subject,” Moore said.

The Manchester Health Department will not take a strong position on the matter at this point, said Health Director Tim Soucy. But the department is in touch with state health officials.

“It doesn’t appear to require widespread notification,” he said.

In a Dec. 18 letter to New Hampshire Health and Human Services Commissioner John Stephen, the head of an anti-fluoridation group urged Stephen to spread information about the ADA advisory.

Gerhard Bedding, head of New Hampshire Citizens for Health Freedom and New Hampshire Pure Water Coalition, said only a handful of media across the country have publicized the advisory. Not everyone will see such news articles, especially mothers of newborns with little free time, he said.

Bedding suggested the state health officials make educational material available to pediatricians, dentists and hospitals; encourge water departments to send warnings with bills; require formula manufacturers to put warning labels on their product; consider providing fluoride-free water to poor parents; and assign a professional to review last March’s report by the NRC.

The ADA stresses that it still supports fluoridation of public water.

Breast milk, the preferable source of food and nutrition for infants, avoids any concerns about fluoride, the ADA said.

For others, ready-to-feed formula is preferable during the first 12 months of life because it helps to ensure that infants do not ingest too much fluoride, the ADA said. If liquid concentrate or powdered formula is the primary source if nutrition, it should be mixed with water that contains little or no fluoride, the ADA said. The ADA recommended that parents consult with their pediatrician, family physician or dentist on the most appropriate water to use in their area to reconstitute infant formula.

In response to an e-mail inquiry, ADA spokesman Fred L. Peterson said he knows of no local health officials who have issued guidelines based on the ADA recommendations. Nor has the ADA received a formal response from any medical organization, Peterson said.