OTTAWA 芒鈧珺次元官网网址� Frustrated indigenous leaders and human rights advocates called out Justin Trudeau on Thursday after the prime minister described mercury contamination at Grassy Narrows First Nation as "very much" an Ontario issue.

Chief Simon Fobister accused Trudeau of "passing the buck" when it comes to the federal government's responsibility for an ongoing toxic leak that has plagued the remote northwestern Ontario community for half a century.

"Trudeau must firmly commit to do everything in his power to clean up the mercury in our river and to ensure that mercury survivors receive proper support and state of the art care," Fobister said in a statement.

If he doesn't, the prime minister will be letting down the people of Grassy Narrows over a health crisis that has plagued residents for three generations, he said.

During a news conference Wednesday in Calgary, Trudeau described the federal government as having only a supporting role to play in the cleanup effort in the northern Ontario community.

"The Grassy Narrows issue is very much a provincial issue,"he said. "But the federal government, under my leadership, is certainly very engaged with the province to ensure we are moving forward in the right direction."

Ottawa has an obligation under international law to respect, protect and fulfil the human rights at issue in Grassy Narrows, said Richard Pearshouse, a senior researcher with Human Rights Watch in Geneva.

This week, a report commissioned by Grassy Narrows and funded by Ontario revealed there is ongoing mercury contamination in the area from a paper mill in Dryden, Ont., that was decommissioned decades ago.

The reserve, located near the Manitoba border, has struggled to deal with poisoning since the mill dumped 9,000 kilograms of mercury into the Wabigoon and English River systems in the 1960s.

Trudeau issued a statement earlier this year indicating the federal government would help tackle the mercury contamination "once and for all," Pearshouse noted.

"To play some kind of federalist game on this is really unfair," he said in an interview.

"For decades now, the community's health has been impacted and that can't be resolved without a cleanup so the federal government is absolutely implicated in this process."

Pearshouse, who paid a visit to Grassy First Nation in December, said Canada is a signatory to a brand new United Nations convention on mercury, known as the Minamata Convention.

"Hopefully quite soon Canada will ratify that convention and when it does, there will be new obligations under international law."

Richard Lindgren, a lawyer with the Canadian Environmental Law Association who is representing the community in a legal matter unrelated to the mill itself, said Thursday he is disappointed by the Trudeau government's position.

There are number of federal responsibilities that warrant further involvement, he said, including fisheries 芒鈧珺次元官网网址� relevant because of the ever-present dangers of mercury contamination in fish that swim in polluted waters.

The federal Fisheries Act expressly prohibits the depositing of harmful substances into water populated by fish, including those species that support indigenous fisheries, Lindgren added.

"If the government is now trying to undertake some constitutional buck-passing and the federal government is now saying it is primarily up to the provincial government ... I am disappointed."

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Kristy Kirkup, The Canadian Press