[Encephalopathy due to organomercuric compounds].

A 27 year old agricultural worker presented about one month after treating cereal seeds with an alcoxyalkyl mercurial derivative, an encephalopathy with a confusional state, a cerebellar stato-kinetic syndrome, an intention tremor and grand mal epileptic fits. Treatment with dimercaprol produced a clinical improvement on the fourth day with a fall in blood mercury from 3.5 mug to 2.2 mug whilst urinary excretion of mercury remained low. A fortnight later the patient was completely cured. Although less common than collective poisoning by ingestion, organo-mercurial encephalopathies due to occupational exposure are a real danger although it is not known whether the relative rareness of published cases is due only to lack of observance of security rules or to individual sensitivity which might be due to increased absorption of mercury through the lungs or skin. This case shows that although alkyl mercurial derivatives are reputed to be the most dangerous, alcoxyalkyl derivatives may also cause encephalopathies. Also, as long as non-toxic substances remain unavailable for use in agriculture, one should emphasise the necessity of careful observance of the security rules during manipulation of these products.