Miscellaneous Studies on the Iodine and Goitre Problem in New Zealand

Abstract

1. Methods for the estimation of iodine in natural products are described.2. Common sea weeds on the Pacific coast of Otago have an iodine content of the same order as similar species on the Pacific coast of British Columbia.3. InCystophora retroflexa, which contains over 0·1 per cent, of iodine, 70–80 per cent, of the iodine appears to be in inorganic or loosely bound combination. Precipitation and colour tests indicate that di-iodotyrosine is also present.4. Observations are recorded of the iodine content of kelp-feeding and other fish.5. Administration of anaesthetics produces fluctuations in the concentration of blood iodine in rabbits, the effect persisting after removal of the thyroid gland. Experimentsin vitrosuggest that only in the case of inorganic iodine could a redistribution of iodine between tissues and serum be brought about by the direct action of anaesthetics.6. New Zealand cabbage possesses goitrigenous properties for rabbits but in a much smaller degree than American cabbage.7. The urinary excretion of Samoans is compared with that of inhabitants of Christchurch Mental Hospital.8. The incidence and course of development of goitre at Christchurch Mental Hospital is discussed.9. Values are given for the iodine content of Otago pigs' thyroids.