A case of acute mercury vapour poisoning.

Introduction Mercury poisoning has been recognized for over a century. Evans' (1962) report of poisoning due to chronic exposure to mercury vapour in industry is well known. Polson and Tattersall (1969) have described other circumstances including the ingestion of mercurous and mercuric chlorides, the subcutaneous, intravenous and intra-arterial injection of elemental mercury and acute exposure to mercury vapour. Chronic mercury poisoning results in (a) exc ssive salivation, the saliva having a foul odour and usually accompanied by swelling, -reddening and tenderness of the lips, gums and tongue or whitening of the tongue followed by blistering, (b) an irregular tremor, not so fine as in thyrotoxicosis, and accompanied by irregular jerking movements commencing in the fingers and spreading to the face and tongue and (c) a tendency to sudden outbursts of anger interspersed with periods of timidity (erethism). Drowsiness, depression, loss of memory and insomnia may occur. Acute mercury poisoning on the other hand produces very different effects and those described in most accounts relate to the ingestion of the salts. There is prompt salivation and a sensation of burning in the mouth, throat and gullet, colicky abdominal pain, nausea and vomiting, bloody diarrhoea and thirst due to dehydration. Renal tubular necrosis occurs and with small or moderate doses there is often an initial diuretic phase but larger doses result in oliguria. Proteinuria and microscopic haematuria occur. Acute elemental mercury poisoning by inhaling the vapour has been reported by Campbell (1948), Glass (1970), Haddad and Stenberg (1963), Hallee (1969) and Milne, Christophers and de Silva (1970) and in nearly all cases dyspnoea has been a