From iodine deficiency to excess : the Tasmanian thyrotoxicosis epidemic of the 1960s

Even though iodine deficiency in Tasmania had been known since the 1830s no full account of the thyrotoxicosis epidemic of 1966-67 has ever been recorded. This personal narrative tracks the history of this epidemic in Tasmania during the 1960s, when it first appeared as iodine deficiency, then as iodine excess, how it was formally recognised and the events leading to its eventual treatment. The addition of iodine into the diet of Tasmanians, initially in bread and then unwittingly through use of iodophors in the dairy industry, resulted in a sequence of events that required unravelling by medical practitioners new to the field but aided by experts from elsewhere. The Tasmanian thyrotoxicosis epidemic was, and continues to be, cited in the annals of the scientific literature as an important medical case study.