Mulcair was in New Brunswick to boost the campaign of provincial NDP Leader Dominic Cardy in a byelection in the Saint John-area riding of Rothesay.
During his visit, Mulcair said the Canadian Association of Petroleum Producers is deceiving the public when it says there are regulations to ensure that shale gas fracking is safe.
"I met with the leadership of the Canadian Association of Petroleum Producers who gave me a lovely brochure, colour, glossy, explaining that they had a policy that all companies doing fracking had to reveal the contents of the fracking fluid," Mulcair said Sunday.
"I said, 'But the companies aren't doing that.' You know what they said? 'Well, we can't force them, they're just our members.'
"That representative of the Canadian Association of Petroleum Producers was out here pulling a con job, trying to make people believe that somehow they were regulating, somehow they had rules that were going to mean something."
Mulcair called on the energy industry to tell the public what is in the fluid that is used in fracking.
"Here's one tough question: If you think that your method of getting to that gas is safe, why won't you reveal the contents of the fracking fluid?" he said. "Because that fracking fluid contains known carcinogens and other very dangerous substances."
The oil and gas industry has argued that fracking is safe and sustainable and provides major economic benefits, an argument environmental groups reject.
The president of association, Dave Collyer, responded to Mulcair's comments by issuing a statement saying association members are expected to adhere to operating practices the association introduced in January.
More importantly, he said the voluntary guideline are not meant to replace existing regulatory oversight, most of which is done at the provincial level.
Disclosure of the types of fluids used in hydraulic fracturing has already been made mandatory in British Columbia, Alberta is expected to follow suit later this year and New Brunswick recently announced plans to require disclosure of fracking fluids, the statement said.
“Shale gas can and is produced responsibly every day across Canada and the United States with more than 175,000 wells fractured safely in Western Canada over the last 60 years," Collyer said.
"Our operating practices demonstrate the Canadian natural gas industry’s continued efforts to ensure responsible resource development."
Mulcair also said he supports the development of a west-to-east pipeline that would deliver energy and generate jobs in Atlantic Canada.
His comments come just over a week after he toured Alberta's sprawling oilsands. At the time, he said he was surprised at the size of the operations and left determined to ensure it gets cleaned up.
He has also traded barbs with premiers from the West after he said that region's booming oil sector was hurting other parts of Canada's economy by driving up the dollar.
Fracking, which refers to hydraulic fracturing, involves the use of water and chemicals to fracture layers of rock to release oil and natural gas.
There has been a public backlash to shale gas development in New Brunswick in recent months, including protests near exploration sites and at the provincial legislature.
(CHSJ, The Canadian Press)
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