Trimethyltin compounds, toxicity

Studies of tin interactions with the yeast Candida maltosa revealed that the cell wall is the dominant site of Sn(lV) interactions with yeast, while lipophilic interactions play an important role in uptake and toxicity of tri-n-butyltin compounds, TBT. TBT uptake resulted in cell death and extensive K+ leakage, while Sn(lV) uptake had no effect. Trimethyltin compounds, (TMT) did not interact with cells. Of the three kinds of compounds, TBT alone altered membrane fluidity. ... 

Tin is comparable in its toxicological behavior to lead and mercury. Bivalent tin compounds generally are more toxic than the tetravalent compounds. Furthermore, organic tin compounds are more toxic than inorganic ones and the trialkyl analogs (triethyltin, trimethyltin, tributyltin) are the most toxic. As the number of carbon atoms attached to tin increases, the toxicity of the organic tin compounds rapidly declines9,77. 

In acute- and intermediate-duration animal studies, signs of toxicity and pathology changes, characteristic of the trimethyltin and triethyltin compounds, were reported. The animal data also confirm the human effects described. 

Tin compounds have great affinity to sulfur. To convert the triorganotin compounds into inorganic tin compounds of low toxicity, the degradation of bis(tri- -butyltin) oxide, trimethyltin hydroxide, allyltri- -butyltin, tin... 

Caution while very useful, many organotin compounds are toxic and should be handled with care. Trimethyltin derivatives in particular are highly toxic and whenever possible should be replaced by the slightly less reactive but much less toxic, tri- -butyl analogues. 

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