Mercury levels enough to impact children’s brain development: report
A new report examining impact of mercury poisoning in Grassy Narrows First Nation says obvious symptoms are the “tip of the iceberg,”
Local members of the Grassy Narrows First Nation prepare signs for an upcoming meeting with government officials. Advocates for Grassy Narrows have been trying to obtain the original cord blood data and other information collected by Health Canada over more than two decades so that their own experts can analyze it. (TODD KOROL / TORONTO STAR)
The level of mercury found in the umbilical cords of babies in Grassy Narrows First Nation was high enough to affect their brain development, according to a new report obtained by the Star.
Between 1978 and 1994 Health Canada tested the umbilical cord blood of 139 infants in Grassy Narrows.
“At these cord blood concentrations, there is consensus from the scientific literature that there would be effects on children’s neurodevelopment,” the report, written by Dr. Donna Mergler, says.
In the report, the leading expert reviews decades of scientific research on mercury’s effects and highlights the hidden impact of contamination on a community.
Mergler said that what recent science tells us is that mercury poisoning occurs at low levels previously thought harmless. At these low levels, a fetus is vulnerable to cognitive damage even if the child’s mother does not show signs of poisoning.
The scientist, whose research specializes in the effects of environmental pollutants such as mercury, wrote it was “surprising” that although world-renowned Japanese researchers had identified many cases of mercury poisoning in Grassy Narrows, there has never been a “scientifically sound” community-wide examination of pre- and postnatal mercury contamination.
Advocates for Grassy Narrows have been trying to obtain the original cord blood data and other information collected by Health Canada over more than two decades so that their own experts can analyze it.
For six months, Health Canada said it would not release the data — even with identifying information removed — citing privacy concerns, according to email correspondence obtained by the Star.
On Thursday, one day after the Star asked Health Canada why the information could not be released, First Nation community advocates received an email from the regulator saying they could have the data.
The original contamination began when a Dryden, Ont., paper plant dumped 10 tonnes of mercury, a potent neurotoxin, into the English-Wabigoon River system between 1962 and 1970. The site of the plant, now under different ownership, is about 100 kilometres upstream from Grassy Narrows.
The locals, who’d built a livelihood as fishing and hunting guides, were told to stop eating the fish. The robust fishing tourism industry was decimated. The fishermen and guides went on welfare.
More than 300 residents (50 of them children) from Grassy Narrows and another community were diagnosed with “symptoms consistent with mercury poisoning” — including loss of muscle co-ordination, vision loss, slurred speech and tunnel vision — and awarded compensation from a Mercury Disability Board. A separate protocol was set up for children that also tests for cerebral palsy and some developmental delays.
Judy Da Silva of the Grassy Narrows First Nation suffers from mercury poisoning. A new report obtained by the Star says the level of mercury found in the umbilical cords of babies in Grassy Narrows was high enough to affect their brain development. (TODD KOROL)
The board was set up as part of a settlement between the company, Reed Paper, and the provincial and federal governments in the mid-1980s. Roughly 700 people who have sought compensation have been turned down.
Locals are concerned that the long-term impact of the pollution is not recognized or even fully understood by the disability board and government officials.
“There are some children being born, they are like five now … but they can’t talk, they talk gibberish,” said Grassy Narrows resident Judy Da Silva. “They’re being sent to specialists in Winnipeg and the specialists can’t figure it out … so there’s effects like that that we don’t understand.”
Mergler was asked to produce her report by the Canadian Environmental Law Association, which is working on behalf of Grassy Narrows. The 61-page report was filed with Ontario’s Superior Court of Justice last week as part of an ongoing lawsuit challenging Ontario’s plans to open up forest land near Grassy Narrows for clear-cutting — a plan that the community alleges will potentially release more mercury into the environment.
Mergler told the Star she is unable to speak publicly about her report because it is before the courts.
The report says that more obvious symptoms of mercury poisoning are the “tip of the iceberg” when it comes to the harmful effects of the metal on human health. Below that tip is a much larger group with subtler yet serious, long-lasting effects.
For kids, mercury exposure in the womb is associated with delayed learning, shortened attention span, memory deficits, delayed language acquisition, poorer motor control or co-ordination.
For adults, the science reviewed by Mergler shows an association between mercury and an increased risk of heart attack and accelerated aging. There is some evidence that mercury exposure increases the risk for Type II diabetes, but it is inconsistent, the report says.
These impacts, the report says, are compounded by socioeconomic conditions.
“If you’ve got kids born with detriments to IQ and neurobehavioural problems, you’ve got parents who are out of work and themselves may be suffering neurobehavioural problems, what does that mean for the kids? It’s a double whammy,” said University of Toronto professor Miriam Diamond, who specializes in human exposure to toxic chemicals and reviewed Mergler’s report for the Star.
Diamond called the report “sound” and “comprehensive” and added it’s an important development in the story of Grassy Narrows because it illustrates how science now appreciates that adverse effects for mercury occur at much lower levels of exposure than originally thought. It also shows a need for a community-wide study of Grassy Narrows, she said.
Mergler’s report also says that Canadian standards for how much mercury is safe to ingest in a day are too high, that the lower guidelines set out by the U.S. Environmental Protection Agency offer better protection against the dangers of mercury.
In 2003 (the last year for which she had data from Grassy Narrows), Mergler found the average mercury intake in the community was above the U.S. safety limit — more than three times the recommended daily dose for men in summer. The analysis included people who didn’t eat fish and would be even higher if those people were not included, she said. (Mergler also points out in her report that the health of people who have stopped eating fish has also been harmed because they are not receiving important nutrients that help with brain and cardiovascular development.)
In an email to the Star, a Health Canada spokesperson said that test results from hair and blood samples of Grassy Narrows residents found that mercury levels declined over the years and by 1995-1997 were “within Canadian safety guidelines for the general population.” As well, that a 2004 research report showed residents’ average exposure to mercury in food was also within Canadian health standards.
Mergler reviewed the same 2004 research report for her recent report and still came to the conclusion that U.S. safety standards for recommended mercury intake offer better protection than Canadian standards. When asked to comment on the assertion that Canadian safety standards are out of date with current research on the impact of mercury on human health the Health Canada spokesperson said Canada’s current tolerable daily intake for mercury is consistent with the position established by the Joint Food and Agriculture Organization of the United Nations and the World Health Organization Expert Committee on Food Additives.
Meanwhile, there is concern in Grassy Narrows that mercury continues to contaminate the waterways. In late May, a provincial government-funded report commissioned by Grassy Narrows said mercury levels in sediments and fish downstream are still dangerously high (while mercury levels in fish have declined over the years, one meal of Walleye from a lake on the river system contains up to 150 times the safe dose of mercury recommended by the U.S. Environmental Protection Agency).The report also raised the concern there is an ongoing source of mercury leaking into the river system.
Last month, the Star published a report that found the province had ignored startling information from retired labourer Kas Glowacki, who said that 40 years ago he was part of a small crew that “haphazardly” dumped drums of mercury and salt into a pit near the old Dryden pulp plant.
The Star then published a report that revealed Ontario’s own former environment minister recommended in 1984 a cleanup of the river system. The government chose instead to let it remediate naturally.
“The Grassy Narrows community has been exposed to high concentrations of mercury in fish for many years and individuals and the community is suffering the effects. It would only add toxic insult to toxic injury to further expose this population to mercury,” Mergler, the scientist, said in her report.