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Therapeutic and toxic doses

A bit more than 500 years ago, Paracelsus was born in Switzerland, in a time when medicine was still viewed by many as the four bodily humours: blood, yellow bile, black bile, and phlegm. Paracelsus was the first to recognize the concept of a dose-response and that certain toxic chemicals, such as metals, when given at a low dose might be curative.

Identify a chemical that demonstrates Paracelsus's important principle of toxicology: "the dose makes the poison". In other words, pick a chemical that is toxic at one type of exposure, but beneficial with other types of exposure. For example, warfarin is used in humans as a drug for blood-clotting and as a poison for rodents.

What is the numeric value for the margin of safety for Fluoride? Show your calculations and explain your reasoning.

â?¢ What is the toxic dose for Fluoride?
â?¢ What is the safe/beneficial dose for Fluoride?

I have decided on fluoride. I understand the math and margin of safety and can explain my reasoning but require help in finding the numbers for the toxic and safe dose for fluoride (e.g. 5mg toxic) so that I can do the calculations by myself. Please provide creditable references for where the numbers were found.

Solution Preview

First you should probably determine which fluoride compound you are going to examine. Fluoride (F-) is a reduced form of the element fluorine (F). Because of its ionic nature, fluoride is found in compounds to balance its charge. The most common are calcium fluoride (CaF2) and sodium fluoride (NaF). Because NaF dissociates much more quickly than CaF2, it is the best for preventing tooth decay, and is probably the one you should use. For more on this see Reeves, Thomas G. "The ...

Solution Summary

Determining the toxic dose of fluoride