MERCURY (QUICKSILVER) Chronic Poisoning (Hydrargyrism):- This may result from (1) continuous accidental absorption (2) excessive therapeutic use, (3) fromrecovery from a large dose, and ( 4) if ointment is used as external application for a long time. Chronic exposure leads to classic triad of gingivitis and salivation, tremors and neuropsychiatric changes. The symptoms are salivation, inflammation of gums and occasionally a blue line at their junction with teeth, sore mouth and throat, loosening of teeth , gastrointestinal disturbances, anaemia, anorexia, loss of weight and chronic inflammation of kidneys with progressive uraemia. Tremors (sometimes called Danbury tremors):- occur first in the hands, then progress to lips and tongue and finally involve arms and leg. The advanced condition is called hatter&;s shakes or* glass-blower&;s shakes, because they are common in persons working in glass-blowing and hat industries. The patient then becomes unable to dress himself. write legibly or walk Properly. The most severe form is known as concussio mercurialis, in which no activity is possible. Mercurial erethism:- is seen in persons working with mercury in minor manufacturing firms. This term is used to refer to the psychological effects of mercury toxicity. These include anxiety, depression, shyness, timidity, irritability, loss of confidence, mental depression, delusions and hallucinations, or suicidal melancholia, or manic depressive psychosis (mad hatter), emotional instability, loss of memory and insomnia. Mercurialentis:- is a peculiar eye change due to exposure to the vapour of mercury. It is due to brownish deposit of mercury through the cornea on the anterior lens capsule. Slit-lamp examination demonstrates a malt-brown reflex from the anterior lens capsule. It is bilateral and has no effect on visual acuity. Renal damage results in membranous glomerulonephritis with hyaline casts and fatty casts in the urine. Kidney is the primary target. Acrodynia or pink disease :- (because it is characterised by a generalised body rash) is thought to be an idiosyncratic hypersensitivity reaction paicularly seen in children. This can be caused by Chronic mercury exposure in any form. The onset is insidious with anorexia, insomnia, sweating, skin Rash and photophobia. Hands and feet become puffy, Pinkish, painful, paraesthetic with peeling of skin. Ref:- k s narayan reddy; pg num:-542,543