A new study published Wednesday in Nature has found that areas of open water in the Arctic are changing the air currents in such a way that mercury from high in the Earth’s atmosphere is being brought down close to the surface. This is causing the toxic mercury to seep into the waters of the Arctic ocean, which in turn could begin to pollute the surrounding oceans, with animals and fish containing toxic levels of mercury.
This problem was discovered recently with the thinning ice in the Arctic, which creates more of these areas of open water that pull down the mercury to the surface. In addition, cracks in the ice are releasing previously trapped pollutants, which are now moving around with ocean currents.
This is especially of additional concern for those who live in the more remote north, as they rely heavily on wild fish and animals caught in the Arctic to survive. And if higher levels of mercury begin to drift downward toward other areas of the ocean, they will not be the only ones at an increased risk of mercury poisoning.
For the majority of people in the world, eating fish or shellfish contaminated with methylmercury (which forms with the deposit of mercury and microorganisms in the water) is the most common way to get mercury poisoning. It is especially threatening to pregnant women, nursing mothers and young children, whose neurological development can be seriously impaired by its toxicity. However, high levels of mercury can harm people of all ages, weakening the heart, brain, lungs, kidneys and immune system.
The leading sources of mercury are from incinerators, forest fires, volcanoes and coal-fired plants, which spew mercury into the air. It then tends to waft northward into the upper atmosphere, where it can then drop down unexpectedly, contaminating areas thousands of miles away from the original source. With the majority of mercury already hovering over the Arctic, it is easy to see how the waters can become toxic as the mercury seeps into the surface of the Earth.
While the study does not take a stand by stating definitively that more mercury is entering the food chain or being depositing in the snow and ice in the Arctic, its findings do indicate the presence of additional mercury at the surface of the Earth. Scientists say that much more research is necessary to determine the amount of mercury pollution this change in air pumping may cause. They also say that these initial findings support the idea that action is needed to reduce the amount of mercury released into the atmosphere by humans.
The Minamata Convention may be the first step toward such an idea. The treaty was recently signed by 94 countries and focused on curbing mercury pollution.
Scientists say that there is much additional research that needs to be done. The next step for this group will be to measure the rates of mercury deposition in various spots in the Arctic and compare them with previous levels measured in the past by Environment Canada at Alert, which has the longest running data set of levels of mercury in the atmosphere in the Arctic. With any luck, this will assist in telling scientist how much of the toxic mercury is seeping into Arctic waters and how worried consumers should be.
By Marisa Corley