Mercury – the Roman messenger of the Gods
Mercury – the first planet from the sun
Mercury – a mineral used by civilization since the days of the Ancient Greeks
Mercury – a neurotoxin whose toxicity has been known since the Ancient Greeks
Remember the Mad Hatter from Alice in Wonderland? He was not a fictional creation of Lewis Carroll’s fertile imagination. Hatters were first sickened and then killed by working with mercury vapors in the curing of felt in the manufacture of hats. “Mad as a hatter” was a common phrase.
Mercury can impair hearing, vision, balance, speech and vocabulary, and muscular control, especially in small children. Even low levels of mercury are harmful to fetuses. Adults can suffer hair loss, an increased risk of heart disease, and memory loss, not to mention poisoning.
We’ve come a long way since I was a child. We used mercury thermometers to take our temperatures. Drop the thermometer and watch it break. That little silver ball was so cute to play with! Cut yourself, and then apply that handy, potent, stinging anti-septic, tincture of merthiolate, also sold as mercuricom. Mercuricom (mercury) poisoning, either through ingestion or excessive dermal contact, was all too common.
The FDA banned the over the counter sale of these formulas in the 1990’s. Many states, including Connecticut, Illinois, Iowa, Maine, Massachusetts, Michigan, Minnesota, New Hampshire, New Jersey, Oregon, Rhode Island, and Washington have banned the sale of mercury thermometers. Some have also prohibited the sale of consumer goods using mercury. Mercury switches are no longer used in new cars.
The 1960’s and early 1970’s witnessed a tragedy in Minimata, Japan. A chemical company discharged mercury wastes into Minimata Bay for almost 4 decades. The mercury got into the food chain with devastating consequences to the villagers who subsisted on a fish diet. Children were born with birth defects and mental retardation. The photos of the children are chilling to look at. Japan criminally prosecuted a few corporate executives for the tragedy, which attracted international attention.
Society is currently concerned about the risks of mercury in dental amalgam fillings, which are a combination of silver and mercury, the use of thimerosal (thiomersol) as a preservative in vaccines, and mercury levels in fish. Early reports linked the thimerosal to increasing rates of autism. Recent studies have discounted the risks both in the fillings and the vaccines. Thimerosal has not been used in the United States since 1999 in children’s vaccines.
Adults, especially pregnant women, should avoid eating shark, swordfish, and albacore tuna because of the buildup of mercury in their fat tissues.
Mercury is a problem in coal power plants. Since mercury does not incinerate and is not biodegradable, it lingers in the environment. Mercury is emitted in the effluents coming out the stacks. The mercury molecules will either fall onto the ground or into bodies of water. In either event, the mercury will work itself into the food chain. These power plants are the largest industrial source of mercury in the environment. A similar problem occurs with the smoke from forest fires.
All this brings us to the law of unintended consequences and those green, energy savings, compact fluorescent bulbs (CFB’s).
By law incandescent bulbs will be history by 2012; no more will be sold in the United States, except perhaps at flea markets, garage sales, and tag sales.
The problem is that each bulb contains mercury, less than 5 mg/CFB, but mercury nonetheless. Throw the old CFB in the trash, and mercury will accumulate in the municipal landfill. Brake the bulb, and mercury will escape. The amounts are miniscule, but the quantities sold are astronomical. WalMart sold 193 million CFB’s between October 2006 and June 2008 while Home Depot sold 75 million in 2007. They all have to be disposed of sooner or later, either properly or improperly.
The mercury vapors in these bulbs have caused injuries to workers, and pose a cumulative risk to society.
However, while the mercury levels have been reduced, science has not yet discovered an alternative to the mercury, which to date is the only source of proper vapor pressure that sheds light efficiently without generating too much heat. Scientists are working on an alternative, but in the meantime it may be a Faustian Bargain, as was asbestos.
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