Jesse Carrie on Mercury...
December, 12 - 2007
My
name is Jesse Carrie, and I’m a Ph.D.
student at the University of Manitoba in
Winnipeg. I’ve been known to upset Neptune,
the god of the sea, for disrespecting his
Arctic waters by always sporting Hawaiian
shirts, although I really think he’s just
jealous of my incredible sense of chic.
Recently I gave a presentation of my work in the Mackenzie River Basin in the Northwest Territories. The main focus of the work is to see how mercury, a very toxic element, is distributed in the system. Furthermore, by looking at other things mercury is found with, we can get a good picture of just how bioavailable the mercury is. If mercury is not in a bioavailable form, then the chances of it having negative effects on creatures big and small (from humans and polar bears to tiny bacteria) become rather small. However, mercury is not something that life can easy be rid of: it is found in literally everything, although in very small amounts- air, water, soil, hair, wood, food; you name it and it will have some mercury content. And even really small amounts, like that found in water, can become a large problem when we get to the opposite end of the food web. Waters generally have mercury levels in the low parts per trillion range, while predators such as beluga can have levels up to several parts per million. In other words, a beluga could have 10 million times the amount of mercury that is found in the water. Health Canada has guidelines that state that we should not consume fish or marine mammals that have levels of mercury exceeding 0.5 parts per million, so you can see that even with low levels of mercury in the water, we still have to watch out for what we eat.
The Mackenzie River is important to the Arctic because it adds the most amount of sediment to the Arctic Ocean, the fourth amount of freshwater and the second highest flux of dissolved materials. This source alone thus has a very strong impact on the ecosystem of the Arctic Ocean, and is the reason I am studying it.
My studies thus far have shown that most of the mercury entering into the ocean comes mainly from the Mackenzie Mountains, as the tributaries deriving from this region contribute the greatest amount of water and sediment to the ocean, and hence mercury as well. The mercury coming from this region is mainly associated with sulfide minerals such as pyrite (“fool’s gold”, an iron sulfide) and sphalerite (a zinc sulfide).
Recently I gave a presentation of my work in the Mackenzie River Basin in the Northwest Territories. The main focus of the work is to see how mercury, a very toxic element, is distributed in the system. Furthermore, by looking at other things mercury is found with, we can get a good picture of just how bioavailable the mercury is. If mercury is not in a bioavailable form, then the chances of it having negative effects on creatures big and small (from humans and polar bears to tiny bacteria) become rather small. However, mercury is not something that life can easy be rid of: it is found in literally everything, although in very small amounts- air, water, soil, hair, wood, food; you name it and it will have some mercury content. And even really small amounts, like that found in water, can become a large problem when we get to the opposite end of the food web. Waters generally have mercury levels in the low parts per trillion range, while predators such as beluga can have levels up to several parts per million. In other words, a beluga could have 10 million times the amount of mercury that is found in the water. Health Canada has guidelines that state that we should not consume fish or marine mammals that have levels of mercury exceeding 0.5 parts per million, so you can see that even with low levels of mercury in the water, we still have to watch out for what we eat.
The Mackenzie River is important to the Arctic because it adds the most amount of sediment to the Arctic Ocean, the fourth amount of freshwater and the second highest flux of dissolved materials. This source alone thus has a very strong impact on the ecosystem of the Arctic Ocean, and is the reason I am studying it.
My studies thus far have shown that most of the mercury entering into the ocean comes mainly from the Mackenzie Mountains, as the tributaries deriving from this region contribute the greatest amount of water and sediment to the ocean, and hence mercury as well. The mercury coming from this region is mainly associated with sulfide minerals such as pyrite (“fool’s gold”, an iron sulfide) and sphalerite (a zinc sulfide).
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