Mercury is a virulent poison that is readily absorbed through the respiratory tract or through unbroken skin. It acts as a cumulative poison since only small amounts of the element can be eliminated at a time. The present accepted threshold limit for Mercury in air is 0.05 mg m-3. (NB. air saturated with mercury vapour at 20°C exceeds the toxic limit by 100 times). High concentration of vapour may cause a metallic taste, nausea, abdominal pain, vomiting, diarrhoea and headache. Chronic effects from continual exposure to small concentrations can cause severe nervous disturbance, insomnia, loss of memory, irritability and depression. Loosening of teeth, dermatitis and kidney damage are possible in severe prolonged absorption.
Mercury can react with ammonia to produce an explosive solid. It can cause severe corrosion problems because of its ease in forming amalgams. Reacts violently with dry Bromine.
Hatters were "mad" due to the effects of mercury vapours
