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From Tasmanian devils to polar bears, it’s all connected
BY MARY O’BRIEN
Almost any saying, even your favorite one, is sometimes false.
For example, one I live by is this: “We are no more and no less than the life around us.”
Fortunately, at the level of an individual and her or his immediate social setting, it’s often false. When somebody, amid brutality, prejudice, rigid ideology or recklessness, insists on behaving with kindness, tolerance, critical thinking or care, that particular somebody succeeds at being more than the life around her or him.
However, at the level of our species (Homo sapiens) and our planet (Earth), you’d be hard-pressed to think of an instance, near or far, in which the phrase is false. Here are three stories — each successive story shorter, each linking eerily to the other, as we are all linked on Earth — for good or ill.
Story #1: Tasmanian devils and brominated flame retardants. The devils are carnivorous marsupials that now survive only on the Australian island state of Tasmania. The devils are experiencing a rare, communicable cancer called devil facial tumour disease, which may finally drive the species to extinction. Scientists have recently found that the devils are carrying in their fat high levels of polybrominated diphenyl ether (PBDE) flame retardants. These chemicals, manufactured by humans as a chemical approach to limiting fire damage in homes and buildings, are linked to cancer, suppression of reproduction, thyroid disruption (PBDEs are similar to the thyroid hormone, thyroxin), reduced immunity to disease and damage to developing brains. Researchers are wondering whether the PBDEs are acting in conjunction with the devils’ immune system that is being genetically weakened due to reduced numbers of devils.
If PBDEs are accumulating in the fat of Tasmanian devils, you’d probably guess they’re everywhere. You’re right. For instance, wastewater sludge at the McMurdo research station, the largest human habitation in Antarctica, recently showed some of the highest environmental levels of PBDEs yet recorded. The wastewater PBDEs came from dust off couches, TVs and other equipment at the base.
At the opposite end of Earth, PBDEs are 71 times higher in Canadian and European Arctic polar bears than in ringed seals, their main source of food. Because PBDEs impact thyroid and sperm function, they are considered a potential cause of the increased hermaphroditism and decreased reproduction that is being observed among polar bears.
In between the North and South Poles, breast milk of U.S. women has been found to be carrying PBDEs at levels approximately 100 times higher than in European women, reflecting greater U.S. use of PBDEs.
Story #2: Loons and mercury. Like watching northern lights, hearing a loon call is one of the most vivid memories of my life: It was a wild, musical wavering across a calm Boundary Waters lake. When invaded by mercury, however, loons become lethargic, their vision reduced, their muscles less coordinated. Adult loons feed their chicks less; and the chicks ride on their parents’ backs less, exposing them to cold and predation. Partly due to mercury contamination, scientists fear the current reproduction of loons may be too low for them to continue in portions of Maine and eastern Canada.
Most mercury is spewed into the world via chlorine chemical manufacturing, because mercury is used to extract chlorine gas from salt. Chlorine is one of the chlorine/bromine/fluorine group of elements which has been eminently useful to the chemical industry and eminently devastating to fish, wildlife (e.g., the devils), humans and our shared stratosphere (e.g., chlorofluorocarbons eating the ozone layer). Running a close second as a mercury source is coal-burning power plants because coal is naturally contaminated with mercury. Third as a source is the melting of auto scrap. In 2003, auto manufacturers agreed to stop using mercury switches, but as older cars continue to be scrapped, mercury continues to be emitted. (It would take less than a minute per car to remove the mercury switches before melting the car).
Story #3: Everyone and greenhouse gas emissions. Greenhouse gas emissions are our species’ contribution to current climate change, and the three main sources of greenhouse gas emissions are coal-burning power plants, oil-consuming vehicles and buildings.
In light of that, consider the links among these stories. Tasmanian devils. Brominated flame retardants. Polar bears. Ringed seals. Breast milk. McMurdo wastewater. Loons. Mercury. Chlorinated chemical manufacture. Coal-fired power plants. Oil-burning vehicles. Severe drought in 2007 in Tasmania. Polar bears depend on ice to hunt for seals and the early break-up of Arctic ice reduces their time for hunting. Climate change is studied at McMurdo research station in the Antarctic…
Can we humans become more than the life around us is saying we are?