A popular kind of coral used in some saltwater fish tanks carries a powerful toxin, and has even sent some people to the hospital.
There have been two cases reported this month, where people who were cleaning their aquariums accidentally released the toxin and reportedly developed shortness of breath or flu-like symptoms.
One entire family from Gatineau, Que., was hospitalized as a result of the coral, reported CBC. Their home was still surrounded by police tape days later.
Another family in Oxfordshire, England, were also reportedly poisoned after a man scraped coral off a rock in his tank while cleaning it. They developed fevers and coughing and also spent a few hours in hospital, according to a report in The Independent.
The culprit may be a type of Zoanthid coral. Some species of these corals, which are increasingly used in saltwater aquarium setups because of their bright colours and overall hardiness, are known to release a toxin when stressed, said Christine Archer, a registered veterinary technician in aquatics at the University of Ottawa.
“I think a lot of people don’t realize that coral are animals,” she said. And some of these animals can sting or produce toxins to protect themselves. The toxin that is causing these problems is called palotoxin, she said.
“It’s one of the most, if not the most toxic chemical that occurs in nature.”
The toxin can cause a variety of symptoms, including difficulty breathing, dizziness, headaches and nausea. The corals release it when they’re stressed, like when being handled or taken out of the water. If a person is affected by the toxin, “Generally, it’s a really sudden onset and you feel really ill and you’re having a hard time breathing.”
Archer recommends that people read up on corals before adding them to their home aquariums, and decide which species they want. If they’re handling potentially toxic coral, they should wear gloves and safety goggles to protect their eyes if they’re taking them out of the water. She doesn’t know of any cases where someone has died because of the exposure, but it does make people very ill.
Health Canada told Global News that it had no reported incidents of poisoning by coral. They also don’t restrict the sale or handling of any coral, but advise that people go to the doctor if they have any symptoms.
A 2015 report from the Centres for Disease Control and Prevention outlined several cases of possible palytoxin poison in aquarium owners in Alaska between 2012 and 2014. In some of these cases, people had apparently breathed in the toxin.
The report called palytoxin a “potent vasoconstrictor” and suggested that it might be useful to develop official guidelines on how to safely handle these corals.
— With files from Abigail Bimman
© 2018 Global News, a division of Corus Entertainment Inc.