Exposure to toxic coral in home aquarium puts Quebec woman in hospital

A woman from Quebec’s Portneuf region is warning aquarium owners to be prudent when handling corals, after being poisoned while she was cleaning out her tank.

Public health officials advise people to stay away from corals altogether

Mélissa Tremblay said she fell ill just minutes after transferring a pair of Zoanthid corals, bottom left, from her home aquarium. (Julia Page/CBC)

A Quebec woman who ended up in hospital after cleaning out her home aquarium is warning others to think twice before adding coral to their fish tanks.

Mélissa Tremblay fell ill last Friday night after she transferred her collection of coral to a larger aquarium in her home in Saint-Léonard-de-Portneuf, an hour northwest of Quebec City.

"I saw a piece of coral break off, but I had no idea it would release something so toxic," said the mother of three.

Within minutes, Tremblay started sneezing.

"It was as if I was having an allergic reaction to a cat," Tremblay said. The symptoms quickly worsened, and the burning sensation spread from her forehead to her lungs.

"It felt like I had swallowed a gallon of bleach," said Tremblay.

Within the hour, she was admitted to Saint-Raymond Hospital for palytoxin poisoning. Palytoxin is a highly toxic substance found in several marine species, including Zoantharia coral. Public health officials told her to get her three children out of the house, even if they weren't showing any symptoms.

"By then, I was in good hands — but I was worried about them," said Tremblay. 

'Don't buy corals'

The Quebec Poison Control Centre is recommending that people stay away from corals altogether.

"All corals are dangerous, and our motto is, 'Don't buy corals'," said Dr. Maude St-Onge, the centre's medical director.

"These are living animals, and if you break them they can release toxins," said St-Onge. She confirmed there have only been two reported cases in Quebec, to date.

Mélissa Tremblay felt a small piece of this Zoanthid coral break under her thumb. (Julia Page/CBC)

Tremblay was released from hospital the following day and hasn't experienced any side effects.

In 2018, a family of seven from the Gatineau region fell seriously ill after transferring Australian Zoanthids in their aquarium.

Quebec City's regional public health director, Dr. Isabelle Goupil-Sormany, said the information about the corals is limited, but problems normally occur when they are being manipulated outside of the water.

She warned that a broken coral, once it is re-immersed, can contaminate the whole tank and become a risk for the entire household.

"So honestly, it's better to be twice as prudent," said Goupil-Sormany.

Call in specialists

Goupil-Sormany said since this is a fairly recent phenomenon, officials are still trying to figure out the best course for coral collectors to follow.

She recommends that people who already have corals in their homes should call specialists if they want to remove them — or at the least wear gloves, a mask and glasses.

"You should really avoid touching them altogether," she said.

Dr. Sormany-Goupil said public health authorities intend to launch an awareness campaign to make sure those who own aquariums, and those who sell them, are aware of the dangers.

The Tremblay family has spent nearly $2,500 to equip their salt-water aquarium.

In four years, Tremblay said she's never had any issues — but she's also never been advised to take extra precautions.

"Anyone can buy these, and the only advice I was given was on how much light they needed," she said.

"It's important they don't sell corals that are dangerous to people. There are so many other options out there."

According to the federal Health Ministry, corals, like other animals, are "exempt from Health Canada's regulatory authority."

"Live animals of any kind, including dogs, cats, goldfish and coral, do not meet the definition of a consumer product under the Canada Consumer Product Safety Act," the ministry said in an e-mail to CBC News.

The Canadian Food Inspection Agency said that "it only requires import permits for aquatic animal species that are listed as susceptible to diseases of concern to Canada. No coral species are susceptible to any of the diseases in our regulations."

Despite the lack of clear guidelines about how to raise and handle corals, Tremblay said she is not ready to give up on her passion just yet.

She will, however, be hiring a specialist to remove the two Zoanthids from her tank.

Her family returned home on Thursday and followed the public health agency's instructions to decontaminate the home by scrubbing every surface with bleach.

"We would have preferred to hire professionals, but our insurance company wouldn't cover the costs," Tremblay said.


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