Research led by Mauro Martinez, PhD, Assistant Professor in the Department of Environmental Medicine at the Icahn School of Medicine at Mount Sinai, was recognized with the Excellence in Environmental Health Science Award at the 2025 NIEHS Environmental Health Sciences Core Centers (EHCCS) Annual Meeting in Kentucky.
The poster presentation titled “Reconstructing Early Life Fluoride Exposure Using a Novel High-Resolution Dentine Biomarker” introduces a groundbreaking method that reconstructs fluoride exposure during pregnancy and early childhood with unprecedented precision—offering new insights into how environmental factors shape health across the lifespan.
Fluoride exposure is common, but existing tests—like measuring fluoride in urine—only reflect short-term exposure. Dr. Martinez and his collaborators developed a new, minimally destructive technique using laser-induced breakdown spectroscopy (LIBS). This laser-based method measures fluoride within dentine, the inner layer of teeth, which grows in distinct layers much like tree rings.
Because baby teeth preserve a record of their growth, this approach allows scientists to reconstruct both prenatal and postnatal fluoride exposure, week by week.
The method was first validated in laboratory studies, which showed a clear, dose-related increase in fluoride within rat teeth. When applied to human baby teeth from children in the United States, Italy, and Mexico, results aligned with reported fluoride intake: children from fluoridated areas had higher fluoride levels than those from areas without fluoridated water.
By creating detailed fluoride “maps” inside teeth, the researchers could see how fluoride accumulated over time—sometimes showing little prenatal exposure but a sharp rise after birth. These insights help identify the critical windows in early life when fluoride exposure may have the greatest impact.
“Our method provides a rapid, sensitive, and spatially resolved way to measure fluoride in teeth without destroying the sample,” said Dr. Martinez. “By establishing teeth as chronological biomarkers of fluoride exposure, this research opens new possibilities for studying how early-life
“This technology represents a breakthrough in understanding how prenatal fluoride exposure can impact children’s health, said Manish Arora, BDS, PhD, MPH. “This is the only approach to reconstruct a temporal profile of exposure during fetal and early childhood. It comes at a time when there are increasing concerns about the risks versus the benefits of water fluoridation,” added Dr. Arora.
Dr. Martinez’s work was supported by the Mount Sinai Center on Health and Environment Across the LifeSpan (HEALS) Pilot Program, part of the NIEHS Environmental Health Sciences Core Centers Program.
Acknowledgments
Funding: P30ES023515, U2C ES026561, U2C ES030859 (NIEHS); R35 ES030435 (NIEHS); R00 HD087523 (NICHD); R56 ES036268 (NIEHS)
Collaborators:
- Mauro Martinez¹, G. Jean Harry², Alejandra Cantoral-Preciado³, Libni A. Torres-Olascoaga⁴, Martha M. Téllez-Rojo⁴, Robert O. Wright¹, Manish Arora¹
¹Icahn School of Medicine at Mount Sinai, USA
²National Institute of Environmental Health Sciences, USA
³Universidad Iberoamericana, Mexico
⁴National Institute of Public Health, Mexico