Back in the good old days hatmakers used to treat cheap fur (often, rabbit fur) with mercury compounds to roughen the fur and to make it mat more easily. This made it usable for felt hats. The treated fur was boiled in acid to thicken and harden it. During another part of the process the hat was steamed and ironed to get it into shape. All of these processes released mercury compounds into the air breathed by workers. The result: Mad hatters syndrome. The symptoms included trembling, loosening of teeth, loss of coordination, and slurred speech. Other effects were more subtle: irritability, loss of memory, depression, anxiety, and personality changes.
At the time no one knew that mercury was the cause. That was then; this is now. Except now two Republican congressmen have issued a report that might lead you to believe that mercury isn't anything to worry about. After years of warnings about mercury in fish, the better-informed congressmen tell us: "There has been no credible evidence of harm to pregnant women or their unborn children from regular consumption of fish."
The report reads as if the fishing and coal industries got together to write it. That's because the real aim of the report is to shoot down regulation of emissions of coal-fired power plants. Coal is possibly the last major industrial source of mercury in the environment. When coal is burned, mercury, a contaminant in the coal, is released into the air whereupon is floats over land and sea before coming down. That's when the problems begin. The mercury gets into the food chain, particularly of fish, accumulates, and then gets into humans when we eat the fish.
The occasion of the report is the impending release of rules to bring mercury emissions under control from coal-fired plants. The Republican congressmen, Richard Pombo (R-Calif.) and Jim Gibbons (R-Nev.), don't want the strict regulation proposed by the Clinton administration as a settlement of a lawsuit. Rather, they want a so-called "cap and trade" system that allows plants to trade emission credits. The problem is that such a system won't do much of anything to bring total emissions down for a decade. The stricter technology-mandating rules would begin to bite within three years or so.
The assumptions and sleight-of-hand used by the report's authors is a catalog of the tactics used by the anti-environmental lobby. First, say there is no problem. Then, say that even if there is a problem it's not being caused by humans (i.e. the humans that run big utilities which give generously to the Republican Party and its candidates). The congressmen regale us with all the natural sources of mercury in the environment. They pretend that if it's naturally in the environment it can't be bad. Well, the environment also has arsenic and lead in it, neither of which is good for you. But, of course, humans are particularly good at concentrating these harmful elements using industrial processes and that is the crux of the whole problem.
The congressmen also tell us that the yearly emissions of mercury have fallen substantially over the last 30 years. What they ignore are the cumulative effects. If we reduce what we add each year to the mountain of mercury already released, this does nothing to lower the toxicity of the mercury already out there. We need to stop adding to what is already in the environment.
Chris Mooney, an independent science writer, does a good job of dissecting the sources of Pombo's and Gibbons' disinformation. Much of it comes from industry-sponsored studies and think tanks (read: propaganda mills). The remaining stuff comes from many government sources which are twisted beyond recognition.
The whole episode makes one believe that the congressmen themselves have been making too many felt hats in an old hat factory. When someone tells you mercury is not all that bad for you, remember the mad hatters.
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