Ciguatera, a type of food poisoning caused by fish caught in tropical and subtropical regions, has been detected at locations on Honshu recently. While the reasons for its emergence are not clear, experts are pointing to environmental changes caused by global warming. Occurrences of the poisoning, which is said to be the most prevalent kind of food poisoning in the world in terms of the number of victims, has been detected in Okinawa Prefecture and Amami-Oshima island in Kagoshima Prefecture for many years.
The reason why the food poisoning has started to occur in Honshu is not clear, but experts have indicated that the habitat of a plankton type associated with the food poisoning could be expanding due to elevated water temperatures, indicating the influence of global warming.
While many aspects relating to the habitats and the ecosystem of the plankton responsible for ciguatera food poisoning are not clearly understood, it is known that the plankton multiplies rapidly once coral dies out as a result of high water temperatures or coastal developments.
A poisonous substance contained in the plankton accumulates in fish that consume it, thereby entering the wider food chain. Several hundred kinds of fish are susceptible to contamination, such as red snapper and barracuda varieties not commonly found in Japan. While these fish are rarely put on the market due to their lack of market value, anglers and fishermen sometimes eat them.
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