Detection of iodine, sulphur and phosphorus in histological thyroid sections by using electron probe microanalysis

Electron probe microanalysis for iodine, sulphur and phosphorus was performed in histological frozen sections from thyroid tissue of 5 patients undergone thyroid surgery for benign disease. Iodine seemed to be localized in the colloid of the thyroid follicles. Phosphorus localized in areas which corresponded with the epithelium of the follicles. Sulphur showed a strong association with iodine both in localization and in relative amounts. It was suggested that iodine and sulphur reflect the presence of thyroglobulin in the colloid of thyroid follicles.