![Lionfish Could be Safe to Eat After All Lionfish Could be Safe to Eat After All](https://images.medindia.net/health-images/1200_1000/fish-memory-booster.jpg)
A new study published in Environmental Biology of Fishes may have an explanation for that. Lead author Christie Wilcox of the University of Hawaii thinks there may be a different reason that so many lionfish are coming up positive on ciguatoxin tests: venom proteins might act as ciguatoxin mimics.
"We already know lionfish produce bioactive compounds — just ask anyone who has ever been stung," she said. "We just don't know a whole lot about what those compounds are or whether they occur outside of the venomous spines."
Ciguatera fish poisoning is a foodborne illness caused by eating certain reef fish whose flesh contains ciguatoxins, small lipid toxins originally produced by single-celled dinoflagellates that live on or near the reef. The toxins themselves are colorless, odorless and tasteless, and cannot be destroyed or removed through any normal process of fish preparation, thus accurate testing is the only way to ensure food is safe to consume. Most current test methods are unable to actually detect the toxin compounds, and instead, focus on what the toxins do to cells to determine if a fish is contaminated.
It struck Wilcox that, at the cellular level, lionfish venom might be difficult to distinguish from ciguatoxins because they have similar activities. She took muscle, skin, spine and liver tissue from invasive lionfish and used antibodies against stonefish venom to detect the presence of venom proteins — and found them. "Lionfish express venom-like proteins throughout their bodies," she said. "We don't know exactly what these proteins are or what they're doing, but we know they're there."
Because tissues for ciguatoxin testing undergo preparation in the laboratory to concentrate the toxins, Wilcox further tested whether these proteins made it through common lipid extraction methods used in ciguatoxin testing. Though the amount was reduced, they could still be detected. "These proteins could be making their way into ciguatoxin test dishes," said Wilcox, "and if they are, there's a chance they're messing up our tests."
Advertisement
The negative impact of false positives is the real issue, says co-author Mark Hixon. "Just the fear and rumor of ciguatera is enough to close a fishery, and that's the last thing we need as we try to encourage people to fight lionfish explosion by eating the invader."
Advertisement