LANCASTER COUNTY, Pa. – Some Lancaster County communities have too little fluoride in their water to effectively fight cavities.

St. Joseph Health Ministries, a local nonprofit organization dedicated to improving children’s health, has created a way for people to learn whether they live in one of them.

The group Thursday launched the “Fluoride Finder” interactive map on its Web site.

Fluoride Finder allows users to plug in any local address and check whether the fluoride in their water system meets standards for the prevention of cavities as recommended by the U.S. Centers for Disease Control and Prevention.

“Many residents may not be aware that fluoride levels are not the same throughout the county,” said Jennifer Thompson, president and executive director of St. Joseph Health Ministries.

“We hope and expect that the Fluoride Finder will help raise awareness about these issues and serve as a valuable tool in the battle to improve oral health in our community.”

According to the CDC, adding fluoride to drinking water can help reduce tooth decay in both children and adults.

St. Joseph Health Ministries reports that 66 percent of the American population is served by public water systems that fluoridate their water.

In Lancaster County, however, only 31 percent of the population is served by such systems.

Thompson said she was speaking to local pediatricians and dentists about two months ago to find out “what resources we could make available to people to educate them about oral health.”

The health professionals Thompson spoke to all mentioned a need for disseminating information about fluoride in drinking water, she said.

The concern is that people living in areas where the fluoride content in the drinking water is below the recommended levels might need fluoride supplements, but they don’t know it.

Using data from the CDC and local public water suppliers, the Fluoride Finder identifies those areas in the county where the fluoride content in drinking water is sufficient, where it isn’t and where there is no information on the water — primarily because it comes from private wells.

Elizabethtown, Mount Joy, Marietta, Columbia, Denver, Ephrata, Akron, Adamstown, New Holland and Strasburg are the larger areas in the county where the fluoride content in the water is considered insufficient.

When people access those areas on Fluoride Finder — in addition to those areas not served by public water — they are instructed to talk to their dentists and/or doctors to find out whether fluoride supplements are needed.

“Until now, it has been difficult for dentists and physicians to know whether a family’s water supply at a given address was fluoridated,” said. Dr. Peter J. Ross, who operates Lancaster Pediatric Dental Associates and serves as St. Joseph Health Ministries’ dental adviser.

“With the Fluoride Finder, we can accurately determine whether a patient has fluoridated water at home, or at a day-care center, a school, at grandma’s house. And knowing this, we can more accurately determine whether a youngster’s fluoride inventory is accurate.”

To access Fluoride Finder, go to St. Joseph Health Ministries’ Web site at www.sjhm.org and click on the “fluoride” icon on the left side of the screen.