HIGHLIGHTS One brand found with iodine content at 10.65ppm, much lower than 20-55ppm set by BSTI Packaging default, methods of iodisation, shape and purity of salt are behind iodine loss Loss of iodine in packaged salt increases with duration of storage Not all brands maintain the BSTI-fixed content of iodine in salts Iodine level reduces if packets are kept open Local brand