Members of Grassy Narrows First Nation will present the 2009 report, which they say should have been made public, at a news conference in Toronto on Monday morning.
The report was commissioned by the Mercury Disability Board, an organization established in 1986 through an out-of-court settlement to assess and manage claims related to mercury contamination in the Wabigoon/English River system. A Dryden-based paper company dumped mercury into the river between 1962 and 1970, contaminating the main source of fish for Grassy Narrows First Nation and Wabesemoong Independent Nations.
In an advance copy provided to CBC News, the report concludes, "There is no doubt that there was high mercury exposure in these two communities in the late sixties and early seventies...There is no doubt that at these levels of exposure many persons were suffering from mercury-related neurologic disorders."
"There should have been extensive examinations and follow-up of these communities from that time forward, and assistance with respect to health and nutrition."
The report's authors, Canadian mercury researchers Laurie Chan and Donna Mergler, also wrote that the Mercury Disability Board's approach "to assess whether or not an applicant has signs or symptoms consistent with mercury poisoning was designed based on the state of science and knowledge of the impact of mercury on human health in the 1980s."
Rate of reported neurological symptoms 'very high'
They reviewed studies by Dr. Masazumi Harada, a Japanese researcher who had visited Grassy Narrows in 1975, and again in 2002, to test residents for mercury contamination and conduct neurological exams.
Chan and Mergler noted that dozens of residents Harada had diagnosed with mercury poisoning "were not acknowledged" by the Mercury Disability Board.
David Sone, a campaigner for the environmental group Earthroots who is working with Grassy Narrows, told CBC News those findings prove that many mercury poisoning survivors continue to be denied compensation.
"The Mercury Disability board is simply using old science and, because of that, they're excluding the majority of people who deserve compensation," he said. "Since that time we've learnt ... that people can be impacted at much lower levels of mercury than we previously thought."
The report also suggests that mercury poisoning continues to affect people in Grassy Narrows and Wabeseemoong First Nations and that they are not receiving adequate medical care.
"We...want to highlight the urgent need to improve the general health of the two communities as the health status of the participants was clearly poor," the authors wrote. "The rate of residents reporting neurological symptoms was very high for such a small population."
Sone said the conclusions would have been presented to the Mercury Disability Board, which includes representatives from Aboriginal Affairs at both the federal and provincial government levels.
In a media advisory for Monday's news conference, Grassy Narrows First Nation says the report "exposes government neglect of mercury survivors."