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Discussion.
Mr. Fleischl inquired concerning Government action to ensure iodisation of salt. Dr. Dempster pointed out that a recent survey by the Health Department of the usage in the community of iodised salt, showed that in various districts up to 90 per cent, of the salt used was iodised, though in other areas it was much less.
Mr. Ferguson asked if there was any difference in the value of “natural” iodine products as opposed to inorganic chemical compounds like sodium or potassium iodides, when given therapeutically. Sir Charles in reply stated that
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sodium and potassium iodides were very soluble and were known to be entirely absorbed, whereas the amount of iodine actually absorbed from the so-called natural sources could not be so accurately estimated.
In reply to a question by Dr. Hubert Smith on the value of salt obtained from sea water, Sir Charles stated that the amount of natural iodides therein was extremely small, but the iodine concentration power of various plankton was very great, and thus the amount of iodine available from evaporating sea water would essentially depend upon the amount of contaminating plankton in the salt obtained therefrom.