Mercury and its effects
How bad is it in the North?
NNSL (July 26/99) - Mercury levels -- on land and water -- are increasing the world over and nowhere is this phenomenon more apparent than in the North.
For Northern people's groups like the Metis Nation NWT, the issue of mercury has become a real concern.
"Mercury is an environmental issue," said environment director with the Metis Nation NWT, Judy Farrow. "Any environmental issue becomes an Aboriginal issue because they have very close ties to the land."
According to Carol Mills, manager for the contaminants division of DIAND, the biggest question that must be asked is why mercury levels have increased in the first place?
"Mercury levels are increasing because of man's activities," Mills replied.
"We are concerned, but not panicking.
"I think the challenge right now is to determine the input of mercury from natural versus manmade activities."
There are three main sources of mercury in any environment: naturally occurring mercury, particularly common in Canadian Shield country; long-range transport, mercury travelling along air and ocean currents; and local sources, such as mining all account for any given mercury levels in one area.
"Even lakes side by side can have wide variations in mercury levels in the water and in the sediments," Mills said. "Right now, we're in the second year of phase two of our Northern Contaminants Program.
"In the first phase (1991-97) we did all the trend and spatial studies and that's when we realized the complexities of the issue. Now we're looking at the effects of mercury and trying to get a better understanding of the main sources of mercury in the Arctic."
Jack MacKinnon, manager of the health protection division GNWT, points out that what might constitute unsafe levels of mercury in the environment for some people might not be true for others.
"Mercury in humans was monitored in the Œ70s and Œ80s in the NWT," MacKinnon said. "Elevated levels were found, but no health-related symptoms of mercury poisoning were discovered either.
"Over the last five years, there has been maternal and umbilical cord monitoring programs in the communities that include testing for mercury.
"This data will allow us to do a comparison to the studies done in the early Œ70s. That information should be available to us early next year."
One of the most compelling theories researchers have been mulling over in recent years has to do with the presence of selenium in the diets of Arctic inhabitants.
"The theory is that selenium somehow reduces the effects of mercury," Mills said. "There have been studies of other Arctic people in Greenland and other countries in the North that show high levels of mercury and selenium in their diets.
"The primary source of selenium is cold water fish and marine mammals, which is also the primary source of mercury. This could explain why we have had no observable effects on the people in the Arctic."