New Brunswick's aquaculture industry is facing questions after an illegal pesticide was found on weak and dying lobsters on the Fundy coast last November.

Environment Canada officials are still investigating how the pesticide, Cypermethrin, made its way onto the lobsters in the Grand Manan and Seal Cove areas.

Cypermethrin is illegal to use in Canadian waters and is toxic to lobsters. But it has been used to kill sea lice in European fish farms.

And that's creating concern about its use in the Bay of Fundy considering some of the dead lobsters were found not far from aquaculture sites last fall. 

David Thompson, an environmentalist, said many people in the area have suspicions about how it got in the water.

"Public feeling is that it probably originated at salmon farm sites, with people attempting to control a very serious problem they had with sea lice," Thompson said.

'We want the public to know that salmon farmers are extremely diligent at protecting marine environment. This is where we grow our fish too.'— Pamela Parker, N.B. Salmon Growers Association

That allegation was strongly rebuffed by the group representing New Brunswick's aquaculture industry.

Pamela Parker, the executive director of the New Brunswick Salmon Growers Association, said the organization does not think any of its members were responsible for Cypermethrin getting into the Bay of Fundy.

And Parker said the group does not condone the use of any illegal pesticide.

"We want the public to know that salmon farmers are extremely diligent at protecting marine environment. This is where we grow our fish too," Parker said.

"We only use products authorized by Environment Canada, and we only use them [in] accordance to prescribed method of treatment. Vets are the only ones who can prescribe these treatments and the fish are under a vet's care, so we take this very, very seriously. " 

Dead lobsters first appeared last November in Grand Manan's Seal Cove, and five days later a fisherman 50 kilometres away in Pocologan found more dead lobsters in his traps.

Soon after that discovery, another 816 kilograms of weak or dead lobster were discovered in Deer Island's Fairhaven Harbour.

Tests found that the lobsters were exposed to Cypermethrin, a pesticide that's illegal to use in marine environments and toxic to lobsters. Environment Canada officials said on Tuesday that human health was never in danger.

Pesticide found in 1996

Environment Canada has launched two investigations into the lobster kills on Grand Manan and Deer Island. The federal department cannot say how long the investigations will take to wrap up.

The fall lobster season in the Bay of Fundy starts in mid-November and stretches into January.

This isn't the first time that the pesticide has been found in the Bay of Fundy.

In 1996, about 50,000 lobsters were found dead in a pound near St. George.

Tests revealed they were exposed to Cypermethrin.

Many people at the time blamed the aquaculture industries in the area for the pesticide getting into the water.