Emedinews - Insight on medicolegal issues: Mercury is not toxic when taken orally as it is not absorbed.

·         Mercury or quicksilver is a liquid metal with a bright silvery luster, which is volatile even at room temperature, and boils at 356.9 degrees.

·         It is 13.5 times denser then water, and 1.2 times heavier than lead. The fumes are odorless and invisible. Mercury is used to making thermometers, lamps, and as an amalgam with other metals for dental fillings.

·         Fatal Dose: An intravenous injection of 0.06g of metallic mercury as a 40 % oil emulsion has proved fatal.  The usual fatal period is 3 to 5 days, but death may take place much sooner or later than this; death has been recorded in half an hour.

·         Metallic mercury when perfectly pure is hardly poisonous. Cases have been recorded where individuals have swallowed a pound or two of the liquid metal as a treatment of chronic constipation without any harmful effects. Mercury is not toxic when taken orally as it is not absorbed. The hazard is from swallowing parts of a broken thermometer are that of the glass and not the mercury. 

(Contributed by Dr Sudhir Gupta)