A study is reporting that children in Miami-Dade County may be exposed to unusually high levels of a radioactive element.

Researchers for the Radiation and Public Health Project blame Florida Power & Light's Turkey Point and St. Lucie nuclear power plants for the level of strontium-90 that they said was found in the baby teeth of 86 Miami-Dade County children that were studied.

Strontium-90 is produced by nuclear explosions and power plants, and it is believed to cause cancer. Researchers say the chemical could be responsible for South Florida having a childhood cancer rate that is higher than the national average.

They want the federal government to conduct its own South Florida study and use those findings when considering whether to renew FPL's nuclear plant licenses.

The group also is sending letters to South Florida families asking for baby teeth so it can track the future health of children with high levels of strontium-90. Baby teeth are studied because strontium-90 imbeds itself in bones and teeth, researchers said.