Cecilia Biancacci1, Damien Callahan 2, Alecia Bellgrove1
1Deakin University, School of Life and Environmental Sciences, Warrnambool, Victoria 3280, Australia
2Deakin University, School of Life and Environmental Sciences, Melbourne Burwood Campus, 221 Burwood Hwy, Burwood, Victoria 3125, Australia
While the health benefits associated with seaweed consumption are numerous, concerns exist associated with possible adverse effects of regularly consuming seaweeds due to potentially high content of heavy metals, arsenic, and iodine. Seaweeds are becoming easily available in supermarkets and groceries stores in Western countries, but in Australia they are almost entirely imported from Asia. Whilst Food Standards Australia and New Zealand (FSANZ) regulates the safety of imported food products, seaweed-specific guidelines exist for arsenic and iodine only and regular testing is not required. We analysed the mineral and metal content of three or four (yakinori) different brands of five commonly imported seaweed products from various Asian countries: kombu, wakame, yakinori sushi sheets, Korean seasoned laver and seaweed crackers. The samples were ground, homogenized, and quantified in triplicate using ICP-MS. Results indicate that levels of Mn, Se, Mo, Cd and Sr may pose a risk to consumers. Iodine content in all kombu samples exceeded the FSANZ tolerable content of iodine for dried seaweed products (1000 mg/kg dry weight), and some brands of yakinori and wakame surpassed the tolerable daily intake of 150 µg iodine/day recommended by the European Food Safety Authority (EFSA); thus all may pose a risk to consumers. Increased monitoring of commercially available seaweed products is desirable to increase data of potential contamination to support further development of regulations on maximum limits and intake recommendations. Furthermore, these results should encourage further exploration into whether ‘home-grown’ Australian seaweeds produced in our unpolluted waters could provide safer food products.