A demonstrator shouts a slogan while holding a blue banner as she prepares to march to the provincial legislature to highlight mercury-related problems on the Grassy Narrows First Nation in northern Ontario. (Chris Young/Canadian Press)Members of Grassy Narrows First Nation converged on Queen's Park on Wednesday to protest against decades of mercury poisoning in their northern Ontario community.

Hundreds of peaceful protesters made their way to the legislature carrying paper fish on sticks and 1,000 metres of blue fabric to symbolize a" wild river."

Grassy Narrows First Nations Chief Simon Fobister speaks with CBC during the protest at Queens park Wednesday. (CBC)"We're demanding justice and action on this issue," Grassy Narrows Chief Simon Fobister said.

Residents suffering the effects of mercury in the water have not been adequately compensated, Fobister said, although their problems in some cases are worse than when the contamination of a local river was recognized more than 30 years ago.

The environmental group Earthroots released a study Tuesday supporting the reserve's argument that mercury problems persist.

A Dryden, Ont., paper mill dumped the equivalent of 9,000 kilograms of mercury into the Wabigoon River between 1962 and 1970, causing long-term health problems for more than 100 people in the community, Earthroots said.

Dr. Masazumi Harada, a Japanese mercury expert involved in the Earthroots study, first visited Grassy Narrows in 1975. He found some residents with mercury levels over three times the Health Canada limit.

Harada visited again several years ago and found 43 per cent of the people who had mercury levels above Health Canada guidelines in 1975 had died. Even residents whose mercury levels were within the limits set by Health Canada were still experiencing mercury-related problems, Harada found.

"It is heartbreaking to hear the stories from the community members whose health has been affected by the mercury poisoning," Angus Toulouse, the Assembly of First Nations Ontario regional chief, said at the Queen's Park demonstration.

"The people of Grassy Narrows have raised their concerns for 40 years now, only to have these concerns fall on deaf ears."

"Would members of the Ontario legislature or the House of Commons tolerate a situation where their families' primary source of water and food was contaminated by a lethal poison? I doubt it very much," said Patrick Madahbee, the Anishinabek Nation Grand Council Chief.

Premier Dalton McGuinty said he wants to take a good look at the Earthroots study before deciding whether to act.

"We have a report, apparently, which says we have a continuing problem, and this contrasts with the federal government saying that things are under control," said McGuinty.

A board was set up in 1985 as part of an out-of-court settlement Grassy Narrows and another community affected by mercury contamination — Wabaseemoong Independent Nations (formerly known as Islington and Whitedog) — reached with the federal and provincial governments and the paper mill.

The Mercury Disability Board administers compensation from a special fund to people whose health was affected by mercury.

Problems persist

Under the 1985 compensation deal, those with mercury poisoning recognized by the board received $250 to $800 a month.

The protesters, however, demanded that governments acknowledge that mercury poisoning is still a problem. They want the federal government to re-examine and tighten guidelines covering cumulative exposure to low levels of mercury.

They also want the government to permanently monitor mercury levels through an environmental centre in the community.

Ottawa stopped monitoring mercury levels in the area in 1999, claiming that the levels of mercury in the Wabigoon River are below federal guidelines.

Mercury has caused more than health problems for Grassy River. Fishing was banned from the river in 1970 after the river was contaminated. This caused an immediate jump in local unemployment — to 80 per cent — a level that has persisted ever since.

"[We want] our issues to be dealt with seriously by the medical establishment in Canada and in Ontario," Fobister said.

The long-term health effects of mercury poisoning include tunnel vision, loss of co-ordination, numbness, tremors, loss of balance and speech impediments.

With files from The Canadian Press