The Biggest Source of Contemporary Mercury Poisoning

In his State of the Union address this week, President Obama drew a line in the sand on toxics. "I will not back down from protecting our kids from mercury poisoning," he stated. A number of listeners might have missed the challenge, imbedded as it was within a myriad of other details in the hour-long speech. Others may have caught something about mercury, but been left puzzling over why this issue was an issue. The enigma is worth deciphering.

Mercury, a.k.a. quicksilver, is one of the oldest toxic materials known to humankind, recognized from antiquity as a slow-working and deadly poison, ever since mines of Spain were worked by the Romans. The naysayers and nabobs of the Neanderthal political right might grudgingly admit mercury isn't particularly good for you. They can even take inspiration from Charles Dickens. He penned the following proto-libertarian tirade in Bleak House: "As to corporations, parishes, vestry-boards, and similar gatherings of jolter-headed clods.....they ought to be worked in quicksilver mines for the short remainder of their miserable existence."

Mercury is an elemental metal that flows as a liquid at room temperature and easily vaporizes, facilitating its ability to wreak toxic havoc. Historically, one of the most widespread and hazardous applications of mercury was in felt-making for fur hats. This 17th century technological advancement made it possible to manufacture hats with passable attributes using low-quality rabbit fur. This proved a godsend for the beaver, whose pelt was a far more desirable starting material for felt, but priced itself out of the market as the resource was depleted through over-trapping. Beaver fur needs no toxic treatment with mercury to make it hold together as felt, in fact, it actually is left discolored and degraded by the process. Just as are the central nervous system cells degrade in humans poisoned by mercury. Mercury felting was a welcomed money-maker for hat factory owners (job creators of their day) whose profit margins were widened by the practice. This was cold comfort, however, for rank-and-file hat-makers. Indeed, fur felt hat-making became synonymous with mental debility. That is why Carroll's Alice in Wonderland character the "mad hatter" is generally taken to be an acknowledgment of how commonly appreciated this toxicity was in the 19th century.

Mercury over-exposure in the hat industry continued well into the 20th century. The problem was controlled as much by changing fashions as anything else. This does not mean that we are free from mercury risk. Sources of exposure still remain. Some of these are esoteric, but nonetheless can be important. Persons who collect antique hats, for example, can be exposed to residual mercury in the felt - a threat that curators of museum-based costume collectors have to take seriously. Victoria and Albert Museum curators have written on this subject. Other hold-over sources of mercury include: out-of-date thermometers and blood pressure monitors, antique mechanical instruments, defunct chemistry sets, and even photographic daguerreotypes (if they are taken out of the case and manipulated). An important and even lethal source of household mercury exposure can occur through home-refining gold. The recipe for disaster is a simple one: mix gold-containing materials with liquid mercury, then boil off the poisonous quicksilver. Mercury can also be an ill-advised component of certain folk remedies. One newer use of mercury has been in energy-saving Compact Fluorescent Light Bulbs (CFLs). Each one contains about 4 mg of mercury (although levels are being reduced); about 10% of that is likely to be release per CFL bulb that is simply dumped in the garbage rather than properly recycled.

The promotion of CFLs is a hot-button item for libertarians, symbolic of yet another dreaded government mandate (like carbon monoxide warning alarms, I suppose). The State of the Union Address call for protection from mercury poisoning discharged a few lightning bolts in the blogosphere on that topic. The irony of course is that even were all the CFLs that have been sold to be dumped each year, the burden of mercury contamination that results would be less than half of one percent of that coming from burning coal in power plants. Although the mercury in coal is present as a natural trace contaminant, combustion release is the major source of U.S. exposure today, a source that can be controlled through appropriate air pollution control technology. Which is what President Obama was talking about.

Just before Christmas this year, the EPA gave the people of the U.S. a rare gift these days - tighter control standards to reduce the release of mercury. Paul Krugman wrote about it in a pithy, Christmas day op-ed for the New York Times, even if oddly titled "Springtime for Toxics." I don't know if subliminally Krugman was doing a mashup with The Producers à la "Springtime for Toxics and Germany." Krugman's piece opens "Here's what I wanted for Christmas: something that would make us both healthier and richer." Maybe a better song link is with "All I Ever Wanted," a 2011 release by the band Airborne Toxic Event. Or maybe it is most fitting that we simply come back to Dickens in honor of his bicentennial. In his story The Haunted Man and the Ghost's Bargain: A Fancy for Christmastime, the protagonist ponders, "If there be poison in my mind...shall I not cast it out?"