5.1 The myth, reality, and history of mercury toxicity  (Page 2/3)

Although elemental mercury was clearly toxic, this did not stop its use in pharmacy for hundreds of years. In the 1500’s mercury was used in the treatment (albeit ineffective) of syphilis. Syphilis was a new disease in Europe; it had been brought back from America by Columbus’ sailors, and was promptly spread through Europe by the French army, amongst others! Syphilis was much more fatal and had more dramatic symptoms than today.

Initially mercury was used as an ointment, but the patients often got worse. Then there was the tub , which was a mercury vapor bath, and even calomel (Hg ₂ Cl ₂ ) was used, but with little effect. These treatments were used for over four centuries, but none provided a cure, despite claims at the time. For example, John Hunter, a doctor who gave himself syphilis by mistake (!) claimed he had been cured, but he actually died of a heart attack during an argument, so it is unlikely the mercury worked. Despite this it became known that “a night with Venus results in a lifetime with Mercury”.

The reasons that mercury was thought erroneously to cure syphilis are twofold:

1. Until 1906 it was difficult to diagnose syphilis. It was often confused with gonorrhea, and therefore it is likely that some people did not have the far more deadly syphilis.
2. Syphilis occurs in three phases, each with remission between the phases. The period of remission between secondary and tertiary phases can be two to three years, and therefore it may appear that a cure is found. Especially as may patients (like John Hunter) died other deaths during this remission phase.

The prevalent use of mercury and its presence in many cadavers, led some doctors to assume that mercury was a natural part of the body. It was not just humans that were treated with mercury, cattle were also treated, and one druggist sold 25 tons of mercury to a single farmer in one year!

The density of mercury and its liquid state at room temperature led to another unusual application that was somewhat more successful, although equally dangerous: constipation. In medical texts of the time it was noted that “mercury is given in the disease called Miserere , unto two or three pounds, and is voided again by siege to the same weight; it is better to take a great deal of it that a little, because a small quantity might be apt to stop in the circumvolutions of the guts, and if some acid humors should happen to join with it, a sublimate corrosive would be made; but when a large quantity of it is taken, there’s no need to fearing this accident, because it passes through by its own weight.”