Organotin Compounds  Systemic effects

   The majority of accidental poisonings involving systemic effects
have been due to occupational exposure to triphenyltin acetate.
Systemic effects reported to have followed
both dermal and inhalation
exposure include general malaise, nausea, gastric pain, dryness of the
mouth, vision disturbance, and shortness of breath
. Hepatomegaly and
elevated levels of liver transaminase activity have been found in some
cases. Recovery has generally been complete but
liver damage has been
known to persist for up to 2 years.

   The hazard associated with the use of organotin compounds was
unmasked by an episode of intoxication in 1954 involving over 200
cases, 100 of which were fatal. The cause was the ingestion of an oral
preparation containing diethyltin diiodide at 15 mg/capsule. It was
suggested, however, that ethyltin triiodide, triethyltin iodide, and
tetraethyltin were present as impurities.
Predominant symptoms and
signs included severe headache, nausea and vomiting, visual and
psychological disturbances, and sometimes loss of consciousness.
autopsies and decompressive surgery, cerebral oedema of the white
matter was found. In many cases, symptoms lasted for at least 4 years;
follow-up information on the subjects involved is not available.
J Toxicol Sci 1990 Dec;15 Suppl 4:125-51  

The neurotoxicology and pathology of organomercury, organolead, and organotin.

Chang LW

Department of Pathology, University of Arkansas for Medical Sciences, Little Rock

The toxicities of many metals, such as mercury and lead, are known to man since the
dawn of civilization. Organic compounds of some heavy metals are known to have a
particular toxic impact on the central nervous system. Organomercury, particularly
alkyl-mercuric compounds (e.g. methylmercury), has a selective effect on the granule
cells of the cerebellum, the nerve cells of the calcarine cortex, and the sensory neurons
in the dorsal root ganglia. The well known Minamata Bay disease is the result of a
massive epidemic episode of human exposure to alkylmercury contaminated food
sources. Mental retardation and other developmental defects are also known to be a
consequence of exposure to this toxic metal. Organic lead compounds have been
employed as gasoline additives and in other industrial purposes. Unlike its inorganic
counterpart, organolead compounds have a more prominent impact on the central
nervous system. Pathological changes of the brain stem neurons have been described.
Organotin compounds have been used in plastic industries and as agricultural
chemicals. Both trimethyl and triethyl tin compounds are found to be extremely
neurotoxic. Despite the similarity of their chemical structures, trimethyl and triethyl tins
have a diversely different toxic property and effects. While triethyl tin is myelinotoxic,
producing edematous and vacuolar changes in the central myelin, trimethyl tin is
neurotoxic, producing prominent toxic changes in the neurons of the limbic system
(hippocampus, entorhinal cortex, etc.). The factors which determine the specificity and
selectivity of the neurotoxic impacts by various organometals are still unknown. In view
that most of the organometals are still widely employed by many countries for industrial
and for agricultural purposes, caution must be made for their proper handling and
disposure to avoid undesirable exposures to workers and environmental contamination
of water sources and food-chain for the common public. Since organometals are
difficult to eliminate from the central nervous system, injuries usually lead to permanent
neurological deficits, such tragedies are frequently long lasting and create not only a
medical problem, but also a social economical problem for the society.