The geochemistry of iodine and its application to environmental strategies for reducing the risk from iodine deficiency disorders (IDD)

The role of iodine in endemic goitre was the first recognised association between a trace element in the environment and human health. Medical intervention techniques such as salt iodisation have been successful in reducing the risks from iodine deficiency disorders (IDD) in many parts of the world. However, much of the effort in eliminating IDD proceeds without a sound understanding of its principal cause - a deficiency of iodine in the environment. This project funded by the UK Department for International Development (DFID) addresses the perceived need for a better understanding of iodine geochemistry so that we can ensure that the small amounts of iodine that are available in the environment are used in the most efficient way. Futhermore, iodine added through environmental supplementation techniques (e.g. adding iodine to irrigation waters) needs to be managed in an effective way to ensure maximum use is made of the added iodine through a better understanding of its geochemical behaviour. This project uses data from BGS case studies in Sri Lanka, China and Morocco plus an extensive bibliography of iodine geochemistry. From this we have created databases on the iodine content of soils, food and drinking water.