Federal Officials See No Cancer Risk From Fluoridated Water

Federal health officials said Thursday that there is no evidence that use of fluoride in the nation’s water supplies should be discontinued.

The statement of continued support for fluoridation came after a panel of experts convened by the Public Health Service called recent studies linking sodium fluoride to the development of a rare bone cancer in rodents equivocal.

“There is no information available at this time that would indicate a need for any change in the Public Health Service policy of continued support for the use of fluorides for the prevention of tooth decay,” said Dr. James O. Mason, assistant secretary for health at the Department of Health and Human Services.

The panel of experts was convened after preliminary results of a two-year study of rats and mice showed a possible association between exposure to very high doses of sodium fluoride and the development of osteosarcoma, a rare form of bone cancer in male rats. The study was conducted by the health department’s National Toxicology Program.

The preliminary results, released in February, found that when 80 rats received doses of 79 parts per million, four contracted cancer. At doses of 45 parts per million, one case was observed in a male rat.

Humans living in areas served by water supplies with fluoride levels considered optimal for prevention of tooth decay drink water containing about 1 part per million, the department said. The recommended upper limit for naturally occurring fluoride in water supplies is 4 parts per million.

Only two cities in Los Angeles County have fluoridated water--Long Beach and Beverly Hills.

Mason said Thursday’s action was one step in a continuing evaluation of the health risks and benefits of fluoridation under way by the Public Health Service. The panel’s findings will be incorporated into a broader review of other animal and human studies involving fluoride now being conducted by a subcommittee established by the department.

David G. Hoel, acting director of the National Institute of Environmental Health Sciences, said in February, after the studies were released, that years of water fluoridation involving “scores of human epidemiological studies” in the United States and in other countries had shown no evidence of a relationship between fluoridation and cancer or other diseases in humans.