Mercury Poisoning

Mercury is a chemical compound that is known as “hydrargyrum” in Latin. This can be translated as "liquid silver". This is exactly the right way how to describe mercury and its appearance. Under normal circumstances, mercury behaves as a fluid that tends to evaporate.


Mercury is used in thermometers and in manometers. Mercury is also present in material, from which dental amalgam fillings are produced. In addition, mercury has a frequent use in industry and in the past, mercury substances used to be administered when treating syphilis.

Mechanism of poisoning

A little known fact is (among the general population) that the ingestion of mercury is not particularly dangerous. Pure mercury relatively quickly passes through the digestive tract and it is excreted in the feces without any significant absorption. Mercury vapors are much more dangerous. Their long-term inhalation in small concentrations leads to chronic poisoning and a high concentration of mercury in the air can cause symptoms of acute poisoning.

Symptoms of poisoning

Acute poisoning is associated with severe damage of the lung tissue causing serious chemical pneumonia. The condition can quickly worsen into a lung edema, when the damaged alveoli allow blood filtration into the lung tissue. The patient suffers from shortness of breath and cough. Acute poisoning can have a life-threatening course with gradual development of an acute respiratory failure. Chronic inhalation of low concentrations of mercury causes a classic triad of symptoms - tremor (caused by mercury deposition in the brain), gingivitis and psychological symptoms (insomnia, nervousness, personality changes). In addition, mercury can damage kidney tissue leading to progressive failure of the kidneys.


Note: Although pure mercury is absorbed in the digestive tract, some its inorganic compounds may absorb, and thus their ingestion can cause symptoms of poisoning such as vomiting, diarrhea and abdominal pain. This way of poisoning is, however, very rare.


When there is a reasonable suspicion of the possibility of mercury poisoning, the physicians can determine the concentration of mercury in blood (rather in acute poisoning) and in urine (rather in chronic poisoning).


Acute poisoning must be treated in intensive care units. It is necessary to secure the airways and in case of need put the patient to artificial lung ventilation. If the affected lung gets infected, it is necessary to use antibiotics. Chronic mercury poisoning is treated using the so-called chelating agents. These are compounds that “scavenge” the molecules of heavy metals and incorporate them into their structures. They “lock” the molecule of mercury to make it harmless and to allow its gradual elimination out of the body.


Jiri Stefanek, MD  Author of texts: Jiri Stefanek, MD
 Sources: basic text sources