Comparative Electrochemical Methods to Determine Fluoride Traces in NaCl

Fluoridated salt is an effective method to reduce dental decay in the population at large, in particular in settings where the more frequently used method of fluoridated water is not feasible due to unreliable water supplies. A salient problem of regular dosage and monitoring of fluoride in salt is its variable level at the industrial level. To evaluate the relative advantages of the present monitoring method used in Mexico, samples of domestic fluoridated salt were analysed by two comparative methods to determine their fluoride content. One of the methods employed was the relevant Mexican Official Norm (based on an acetic acid, sodium chloride, trans-1,2-diamine, cyclohexane N,N,N′,N′ tetracetic acid buffer solution) and the other was an alternative electrochemical methodology (based on an acetic acid, sodium chloride, sodium citrate buffer solution). The cost of the chemicals involved and simplicity of the alternative method, along with the equivalent precision of its results, makes it an interesting choice for the large scale analysis of fluoridated salt.