Food Standards Australia New Zealand (FSANZ) conducted a survey of iodine levels in seaweed and products containing seaweed, in consultation with the Australian states and territories. The 'Survey of iodine levels in seaweed and seaweed containing products' shows most seaweed and seaweed products have safe levels of iodine, but there are some products with very high iodine levels that may be unsafe for human consumption.
The survey was prompted by an increased number of reported human thyroid dysfunction cases linked to high iodine intake. The high intake was considered to be associated with consumption of a soy beverage, Bonsoy. The high iodine levels in the beverage were attributed to the addition of seaweed (kombu, Laminariaspp) during manufacturing.
At the same time as the Bonsoy incident, high levels of naturally occurring iodine in seaweed were identified in Heng Fai Dried Seaweed Brand ® (Sargassum fusiforme), with a voluntary food recall of this product in March 2010.
Another survey looked at iodine levels in beverages enriched with seaweed. The findings were reassuring, indicating that iodine levels in the beverages analysed were well within safety margins.
We advise consumers, particularly pregnant and breastfeeding women, not to over consume brown seaweeds with potentially high levels of iodine.
FSANZ has also provided the Australian Quarantine and Inspection Service (AQIS) with risk assessment advice about iodine levels in brown algae/seaweed vegetables. AQIS has subsequently listed brown algae/seaweed vegetables on the imported food ‘Risk List’.
Download a copy of the survey
Survey of iodine levels in seaweed and seaweed containing products available in Australia [ word 197 kb | pdf 194 kb]
Fact sheet: Advice on brown seaweed for pregnant women; breastfeeding women and children