Generally in the form of fungicides, the majority of which are now banned in the
UK and in France. Ethylmercury phosphate, 2-methoxyethylmercury acetate and phenylmercury
acetate are organomercurial fungicide seed treatments for cereals and fodder beet,
permitted for use in the UK. In France, only silicate of methoxymethylmercury is
authorized for use as a crop seed dressing. This chemical group comprises a large
number of compounds which are not detailed here.
Animals most affected
Cattle, sheep, pigs, (other species).
Ingestion of the agricultural product or
of treated seeds. Poisoning by these compounds has become increasingly rare. The
different compounds may be grouped into two main categories:
arylmercurials (methyl or ethyl): following ingestion they are graduallyincorporated
into the body of the animal (notably into muscle and the CNS);
alkyimercurials (phenyl): less well retained by the body following ingestion
and excreted by the kidneys.
The tendency for these compounds to accumulate in tissues makes meat unfit for consumption.
Extremely toxic compounds which accumulate
in living organisms.
Oral doses in mg/kg:
dependent on the species and the particular compound involved
Silicate of methoxyethylmercury:
Clinical features Neurological effects
Acts upon the CNS:
incoordination, ataxia, followed by
prostration and convulsions.
eczema, pustules, ulcers, possible hair
Occasional (other) effects
anorexia, weight loss;
epistaxis, haematuria, blo'ody diarrhoea.
petechiae or haemorrhages, more ol generalized;
necrosis of the intestinal mucosae, liver and the CNS;
No antidote. BAL or sodium thiosulphate may,
in the opinion of some contributors, be used effectively as chelating agents.