Puffer fish has been on FDA's Automatic Detention List since 1980, because the product "...appears to contain the poisonous and deleterious substance tetrodoxin." FDA's certification program requires the agency to audit sample proposed entries. FDA's concerns prior to the decision to allow the importation of Japanese puffer into the United States, were associated with the sampling of puffer fish and the analytical methodology to determine the absence of tetrodotoxin. For puffer fish there is no adequate sampling scheme that can assure a safe lot, since any single fish may contain a lethal dose of the toxin. While progress has been made in analytical methodology to determine the presence of toxin, it is still inadequate. These concerns are compounded by the fact there is no known antidote for tetrodotoxin.
The four years of discussions between the FDA and the Japanese Ministry of Health and Welfare (MHW) officials were concerned with the actions the Japanese government would take to assure that FDA's concerns would be adequately addressed, thus ensuring the safety of imported puffer fish.
Puffer fish is an easily recognized type of fish due to ability to transform and enlarge its body in a split of a second. There are more than 120 species of puffer fish which live mostly in the warm waters of the Indian, Pacific and Atlantic Oceans, with only 30 species that are living in the freshwater. Some species move from marine to brackish or fresh water during the breeding season. Although number of puffer fish is stable in the wild, they are vulnerable due to overfishing, pollution of the ocean and loss of natural habitats.