The health impacts of mercury poisoning in a northern Ontario First Nations community are worse now than when fishing in waters contaminated by the substance was first banned there 40 years ago, according to a report released in Toronto Tuesday.

It was exactly four decades ago, on April 6, 1970, that fishing was banned on the Wabigoon River because of mercury contamination caused by a paper mill upstream in Dryden, Ont. — owned by Reed Incorporated and subsequently Great Lakes Forest Products Limited.

The mercury poisoned fish in the Wabigoon and English river systems and continues to harm the health of more than 100 people living on the Grassy Narrows First Nation, Japanese mercury expert Dr. Masazumi Harada concluded in his report.

Harada also examined the effects of mercury contamination in another community that uses the same river system — the Wabaseemoong Independent Nations (formerly known as Islington and Whitedog).

When Harada first visited the reserves in 1975, he found people with mercury levels over three times the Health Canada limit.

Mercury is a potent neurotoxin and a persistent pollutant.

Health impacts include:

• Tunnel vision.
• Loss of co-ordination.
• Numbness in the extremities.
• Tremors.
• Loss of balance.
• Speech impediments.

Compensation criteria

Fewer than half of the people who Harada said are affected by mercury are receiving compensation from the Grassy Narrows & Islington Band Mercury Disability Board, said residents of Grassy Narrows who attended the press conference announcing the English version of Harada's report.

"One of the really specific things that we're looking for was the provincial government to come back to the table regarding the mercury issue," Grassy Narrows resident Judy Da Silva said in an interview.

The Mercury Disability 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 two paper companies.

It administers compensation from a special fund to people whose health was affected by mercury contamination.

The board has its own measure for judging compensation, said chairperson Margaret Wanlin.

"To what degree is mercury impacting people's ability to conduct their daily lives, whether that was hunting and fishing, or doing crafts or working in their family home and doing the natural things of their life," Wanlin said.

"So, it's really measuring extent of impairment, and we're also aware that over time, there can be some advancing of these conditions so people can have a subsequent evaluation, a neurological assessment, two years later."

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

Some environmental groups are calling for tighter guidelines on mercury safety, but Ontario Premier Dalton McGuinty said Tuesday he will wait to read the report before making any decisions.

"It seems that we have conflicting data and information," McGuinty said at an event in Peterborough.

"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."

Health Canada stopped testing in 1996

When Harada returned to Grassy Narrows in 2004, he found that 43 per cent of the people who had mercury levels above Health Canada guidelines in 1975 had died, said the environmental group Earthroots in a news release.

He found that even the residents whose mercury levels were within the safe limits set by Health Canada still experienced mercury-related health problems. Of the 156 people from Grassy Narrows and Wabaseemoong with levels below the guidelines whom Harada's team examined in 2004, 89 per cent had Minamata disease, a type of mercury poisoning, Minimata disease with complications or possible Minimata disease.

Residents of Grassy Narrows say Health Canada stopped testing for mercury in their community in 1996, claiming it was no longer a problem because mercury levels have fallen below its safety guidelines.

Earthroots and the citizens group Free Grassy Narrows want governments to:

• Acknowledge that mercury poisoning is still a problem.
• Strengthen federal guidelines on cumulative exposure to low levels of mercury.
• Permanently monitor levels through an environmental centre in the community.

Wanlin said it's often difficult to differentiate between the signs of aging and the effect of mercury poisoning.

She added the board is currently reviewing all the international research on mercury to see whether any changes need to be made to its policies.

Between 1962 and 1970, the Dryden mill dumped 20,000 pounds of mercury into the Wabigoon River, the groups said.

On Wednesday, residents of the Grassy Narrows and their supporters plan to rally at the provincial legislature to urge the government to pay attention to the mercury issue.

With files from The Canadian Press