Fluoride content in table salt from the Element Project in Mexico City.

Objective: This study evaluated fluoride content in table salts from participants' households of the Element project, comparing them with the Mexican standards of fluoride content in table salt (200 to 250 mg/kg).

Materials and methods: Salt samples were collected from households of mother-offspring pairs participating in Element. Salt samples were analyzed in duplicates using a combination fluoride ion-selective electrode and a pH/ISE meter.

Results: Among 657 samples from 14 brands, fluoride varied from 0.016 to 477.9 mg/kg with a median (IQR) of 142.5 (136.9). Of salts labeled as fluoridated or containing fluoride (n= 607), we found that 72.8% (n= 442) had fluoride content below the recommended range and 13.8% (n= 84) were above the Mexican norm. Only 81 salt samples (13.3%) fell within recommended limits.

Conclusion: Future studies with representative sampling are needed to evaluate table salt fluoride content, especially in high-fluoride areas, to inform potential adjustments to the current monitoring program.