HALIFAX -- Ecological groups will argue in Federal Court this week that a decision by Environment Canada to approve the production of genetically modified salmon eggs should be overturned, saying the process was cloaked in secrecy and could set a dangerous precedent.

The Ecology Action Centre and Living Oceans Society contend that the federal department did not follow its own legislated rules and conduct a full risk assessment before clearing a U.S. company to produce the eggs in Prince Edward Island.

Mark Butler of the Ecology Action Centre in Halifax said the risk is that if the genetically modified salmon escape from land-based tanks, they could mix with wild stocks with unknown consequences.

"Once that fish breeds with another wild salmon, you can never put the genie back in the box," he said before leaving for the two-day hearing in Ottawa.

"This technology slightly increases the growth rates of fish, so they get to market faster. Compare that benefit to the risk to wild stocks. If genetic contamination did occur, it would have a huge impact on the recreational fishery."

Boston-based AquaBounty Technologies says it has developed a way to make Atlantic salmon grow twice as fast as normal by modifying eggs with genes from chinook salmon and an eel-like fish called the ocean pout.

It has been seeking regulatory approval in the United States since 1995. And while neither Canada nor the U.S. has approved the fish for human consumption, Environment Canada's decision to green-light the manufacture of eggs in Souris, P.E.I., is seen as a significant milestone.

Kaitlyn Mitchell, a lawyer with Ecojustice who is arguing on behalf of the groups, says they are making a unique legal argument under the Canadian Environmental Protection Act dealing with animate products of biotechnology.

"This is significant because we're talking about potentially the first genetically modified food animal in the world," she said. "It's important that the government gets it right from the beginning."

Butler said he hoped the case would be a chance for the newly elected federal government to change course on the approval, saying that because the Liberals under Prime Minister Justin Trudeau appear to be "taking a new approach to climate change, they might also take a new approach to this decision."

A spokeswoman for Environment Canada said she couldn't discuss the case because it was before the courts, but maintained that a thorough risk assessment of the salmon was done.

"This risk assessment concluded that there were no concerns identified to the environment or to the indirect health of Canadians due to the contained production of these GM fish eggs," Maria Ivancic said in an emailed statement.

The suit contends the government failed to take into account information required by legislation, including test data on toxicity, invasiveness and pathogenicity.

AquaBounty's plan is for the genetically modified fish to be grown in Panama and then later in other facilities, pending approval by U.S. authorities.

Ron Stotish, the company's CEO, said in a statement that, "AquaBounty is confident the Government of Canada will prevail in this action, and we believe the case brought by the two non-governmental organizations is completely without merit."

In a November release, AquaBounty said Environment Canada's approval was based on a close study of its hatchery facility in P.E.I., and the opinion of a panel of independent scientific experts through the department of Fisheries and Oceans.