STUDIES ON THE TRANSFER OF THIO-OXAZOLIDONE-TYPE GOITROGENS INTO COW'S MILK IN GOITRE ENDEMIC DISTRICTS OF FINLAND AND IN EXPERIMENTAL CONDITIONS

Abstract

ABSTRACT In six out of nine milk specimens from farms in a goitre district of Finland and in five out of eight from two other goitre districts, 1-5-vinyl-2-thio-oxazolidone (VTO) was found in amounts corresponding to concentrations of 35 to 100 μg/l by means of a slightly modified method of Kreula & Kiesvaara (1959). Applying this modification it was found that even that part of VTO could be assayed which changes during the storage of the milk samples, but still retains its goitrogenic activity. Later on, when the cruciferous weeds that grow abundantly in the pastures and meadows of these farms had been destroyed, VTO was no longer demonstrable in the milk samples. These weeds were shown to contain large amounts of VTO both in the green parts and seeds. The concentration of VTO found in the milk exceeded the level necessary to explain the goitrogenic effect of this milk when fed to rats in long-term experiments. According to preliminary studies, this amount would even induce a goitrogenic effect in man. Thus it might well be responsible, at least in part, for the goitre endemic in these districts.