Estimate of the digestibility, assimilability and intestinal permeability of butyltins occurring in wine.

An estimate of the digestibility and assimilability of butyltins occurring in contaminated wines (Port, red and white) was obtained by means of in vitro studies of gastrointestinal digestion. The influence of the wine matrix on the intestinal permeability was explored by studying the accumulation of butyltins in Caco-2 monolayers either when these species are dissolved in buffer only or in the dialysates of digested wines. Some important information about the fate of the butyltin compounds ingested from contaminated wines could be achieved. Only a very small fraction of the ingested DBT and TBT, the two most toxic forms, appear to be able to reach the epithelium as judged by the small dialyzable fraction found (<2%). This is probably independent from the food/drink matrix introducing these contaminants, since the influence of the involved enzymes appear to be dominant, especially for DBT and TBT. Additionally, the intestinal permeability of the three butyltins was also very low, the wine matrix possibly having a hindrance effect in a few cases.