Nordic countries publish new report on food safety in seaweed

Since 2020, the food safety inspectorates of the Faroe Islands, Iceland, Denmark, Norway, and Sweden have worked together to develop a common Nordic approach to risk management of food safety in seaweed and kelp. This collaborative project has now come to an end with the publication of its final report, which highlights the chemical and microbiological risks related to the commodity.  

The use of seaweed and kelp as food is increasing in the Nordic countries, as well as in other countries in Europe. Although seaweed is the biggest aquaculture product worldwide, there is a lack of international standards and regulations for food safety in such type of food. Moreover, little is known about the commodity’s potential risks and benefits to human health.  

The Nordic project highlights in its report the necessity, among other things, to develop a harmonized regulatory framework where seaweed and kelp are classified as a specific group of food, with subgroups for different species.

The report contains updated knowledge about food safety in seaweed and kelp, with special emphasis on Nordic conditions. It describes, among other things, existing production and risk management, which Nordic species are relevant for use as food, their new food status and analysis data from the various countries for different contaminants.    

Iodine, cadmium, and inorganic arsenic are the most important food hazards relevant for seaweed harvested in Nordic countries, though the magnitude of their presence can vary greatly between and within seaweed species, and can be affected by age, growing conditions, and processing methods.  

Iodine is an essential micronutrient, however, both insufficient and excessive intake may lead to health issues. As some food products based on seaweed can contain very high levels of iodine, the report classified it as a potential hazard.  

Because seaweeds are high in polysaccharides, they tend to become loaded with trace metal elements, such as cadmium and arsenic. The exposure to these two heavy metals has been reported to be associated with diabetes, cardiovascular disease and cancer, among other issues.  

Other important food hazards identified in the report are lead and mercury, Bacillus in heat-treated products, kainic acid in dulse (sea lettuce flakes), and allergens.  In general, throughout the Nordic countries, brown algae have the highest iodine content, with the highest concentrations found in the species sugar kelp, winged kelp, oarweed, and tangle. Red and green algae species have lower levels of iodine than the brown algae, except for the red algae wrack siphon weed. Oarweed can have exceptionally high levels of inorganic arsenic, while cadmium levels are highest in several brown and red algae.  

Although more research is needed, the Nordic report can be used as a guide for the European Food Safety Authority (EFSA) as well as the industry.