The clean coastal waters of New Zealand’s Otago Coast are the source of Thompson’s high potency Kelp. New Zealand’s coastal waters are clear of both pollutants and radioactive isotopes. This is not the case for seaweeds from other parts of the world, some of which can be shown to have isotopes of Iodine, Uranium and other radioactive materials, often originating from Chernobyl. Because of a lack of industrial pollution in the region, Thompson’s Kelp is also free of all petrochemical materials. The species of Kelp used, Macrocystis pyrifera, grows around the southern North Island, the South Island and islands such as Stewart Island. The leaves and stem of Macrocystis are harvested by hand and sun dried in the clear air of the East Coast. Sun drying is considered a superior form of processing, as it ensures retention of full nutrient value.