PPT Slide
The Mad Hatter's madness (odd conception of time and other idiosyncrasies) were direct results of his occupation. In the 19th century, hat makers used to treat felt and fur hats with a mercury compound that killed bacteria, thus keeping them from rotting. Hatters used mercury, because it was a potent poison. Not only does it kill bacteria in hats, when inhaled or taken in through the skin, it has a particular affinity for brain tissue. The damage it does to brain cells can be devastating and irreparable.
Today we know that hatters became "mad" from breathing mercury fumes and getting mercury on their hands. "Mad Hatter's disease,"or erythism, is now a recognized psychiatric syndrome consisting of a wide range of neurologic and psychiatric disturbances.
Chemists classify mercury as a heavy metal. As a rule, heavy metals are nasty in the human body; even small amounts are toxic and persistent. Health problems caused by low-level chronic exposure to heavy metals may take years to appear. By the time symptoms occur, it may be too late to do anything about them.