Since lionfish invaded the Caribbean and Atlantic, there have been programs promoting the consumption of lionfish in an effort to control them. There have been lionfish cookouts following lionfish derbies, restaurants serving lionfish, and even fishermen selling and exporting lionfish filets. But in 2012, Florida Sea Grant and the FDA found detectable levels of ciguatera toxins, or “CTX’s”, in lionfish samples. Have lionfish been promoted as food when they are actually unsafe to eat? A recent study explores the lionfish ciguatera controversy and finally provides some answers.
What is ciguatera?
Ciguatera is a toxin produced by dinoflagellates, a type of plankton. The dinoflagellates that produce this toxin are found in tropical and subtropical regions such as the Caribbean and South Pacific islands. So how is a toxin produced by plankton a problem for humans? This toxin “bioaccumulates” meaning that small fish that eat seaweed covered with this plankton may gain a low amount of toxin, but medium fish that eat those small fish then gain a medium amount, and large predators that eat those medium fish now have a large amount of toxin that has built up by being passed up the food chain. The toxin doesn’t harm the fish, but it is harmful to humans when we eat the meat of “ciguatoxic” fish. It is colorless, odorless, and isn’t broken up by heat when fish are cooked. Ciguatera poisoning has no cure and causes gastrointestinal and neurological symptoms that usually go away within days or weeks. Lionfish aren’t necessarily “large predators” but they eat a lot of fish and a lot of different kinds of fish, so they are suggested to potentially act as “apex predators,” leading to the possibility that they can carry high amounts of ciguatera toxin.
Are lionfish toxic to eat?
A study by Florida Sea Grant and the FDA found ciguatera toxins in lionfish, yet there have been no reports of ciguatera poisoning from lionfish. So what is the real story? Are lionfish safe to eat or is it just a matter of time before someone gets poisoned from eating lionfish? A new study by Christie Wilcox and Dr. Mark Hixon provides an interesting explanation. If you have heard of a lionfish, you probably know that they contain venom in their spines that cause painful injuries. Interestingly, some of the symptoms of a lionfish “sting” are similar to those of ciguatera poisoning. This led researchers to wonder: are lionfish toxins and ciguatera toxins so similar that ciguatera tests on lionfish are inaccurate? They suggest that toxins found in lionfish spines can also be present in the tissues usually used to test for ciguatera. So if lionfish toxins are similar to ciguatera toxin, ciguatera tests may return false positives in lionfish. This sounds like good news: lionfish may not be positive for ciguatera after all. But wait, if there is just a different toxin causing the positive test results, is that really “good news”? Actually yes. There is one important difference between ciguatera toxin and lionfish toxins: ciguatera toxins don’t break down from the heat of being cooked, but lionfish toxins do. That is why lionfish spines are harmless, well other than their sharpness, after lionfish are cooked. This means that if lionfish toxins are found in the meat of lionfish, that meat is safe to eat once it is cooked. Researchers suggest that future ciguatera test should be performed on lionfish once they are cooked to get accurate results and clear up this controversy. Personally, I have eaten lionfish more times than I can count without any problems. I plan to continue eating lionfish whenever I can. They taste delicious and you can feel great about helping reefs while you eat them!