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A clear and present danger: grave mercury poisoning at Grassy Narrows

The Story

Minamata, Japan, became synonymous with mercury poisoning in the 1950s. For years, many in the factory town were crippled by a mysterious illness. More than 100 died. The poison was eventually traced to fish from Minamata Bay, where a chemical company had dumped tonnes of mercury-contaminated waste. This investigation by CBC Radio's As It Happens asks: "Could the name Kenora become as infamous as Minamata?" Secret government documents suggest it might. The Ontario government has downplayed the mercury contamination in the northwest corner of the province. But a 1972 study prepared for the cabinet says fish from the St. Clair River and English-Wabigoon waterway are as contaminated as fish from Minamata. A leaked federal report says the health of the Grassy Narrows and Whitedog residents "must be considered at risk." 

Medium: Radio
Program: As It Happens
Broadcast Date: Nov. 6, 1974
Guests: Leo Bernier, George Kerr, Barney Lamm, Shinobu Sakamoto, Eugene Smith, James Stopps, Tadao Takeuchi
Host: Barbara Frum, Alan Maitland
Duration: 15:11

Did You know?

• The Minamata poisoning came to international attention in 1956. First to show the effects were fish-eating cats that started moving erratically, losing their balance and screeching. Soon humans, including newborns, started exhibiting the effects of so-called "cat dancing disease." By 2003, the Japanese government had designated about 3,000 people as victims of severe mercury poisoning, or Minamata disease. Japan's Chisso Corp. had discharged an estimated 27 tonnes of mercury compounds between 1936 and 1958.

• Prolonged exposure to mercury can, according to Environment Canada, cause damage to the brain, spinal cord, kidneys, liver and developing fetus. Symptoms include impaired senses and balance, shaking, slurred speech, balance problems, numbness and tunnel vision. Severe, prolonged exposure can cause personality changes, stupor, coma and death. In 2001, experiments conducted at the University of Calgary showed that mercury - unlike other heavy metals - can cause brain cells to shrivel.

• When dumped into waterways, mercury settles in the top layer of sediment on the lake or river bed. Micro-organisms convert it into methylmercury - more toxic than the inorganic metal form - and it enters the food chain. It accumulates over time in the tissue of fish and shellfish. Generally, the highest concentrations are found in the oldest and largest specimens. High mercury levels in loons in Nova Scotia have been linked to their dramatically decreased birth rate.

• As It Happens researchers had a a difficult time getting any information from the Ontario government about the province's mercury problem. Requests for data were shuffled between various ministries and a lawyer hired by the government to sue Dow Chemical Co. over its mercury emissions, with little results.

• Two days after the CBC program aired, the Ontario government released the 1972 report. Health Minister Frank Miller told reporters it had not been released earlier because it was only a "working document" for a study published in April 1973. Opposition parties jeered at Miller's explanation. "How dare you not bring (the report) to public attention for more than 2 ½ years?" shouted NDP leader Stephen Lewis in the legislature.

• Questions were raised about the 1972-1973 coroner's inquest of Thomas Strong, a trapper-guide from the mercury-contaminated area who had eaten a lot of fish. The inquest concluded that Strong died from a heart attack. No autopsy was performed but blood tests showed he had an abnormally high mercury level. Dr. James Stopps, senior consultant on environmental health for the Ontario government, testified the blood sample must have somehow been "contaminated" with mercury after Strong's death.


Mercury Rising: The Poisoning of Grassy Narrows more