I think toxicology is one of the coolest of the ~ologies, so my ears always perk up when there’s a news story with a toxicology angle.
Right now we have one here, because a local school had to be shut down because of mercury contamination. That isn’t a completely unheard-of event…two schools in Mississippi and a library in Indiana had mercury problems last month.
Mercury cleanup is an expensive proposition, and the kids in DC did a lot of damage, spreading somewhere around 250 milliliters of it around the school. (Apparently they thought it looked like something from a Terminator movie when they flung it off their fingers.)
Mercury is fun. I don’t know anyone my age or older that doesn’t have a story or two about playing with a broken thermometer or barometer and chasing those slippery silver balls around a tabletop or floor. The problem is that the amount of mercury in a thermometer (about half an ounce to an ounce) is sufficient to kill a small child.
Mercury’s chief hazard is chronic inhalation of the fumes. In household poisonings, you usually find that somebody breaks a thermometer or something, the mercury vaporizes and persists in the environment (spread through the house by the vacuum cleaner in some cases) and the family breathes it in. Kids are at biggest risk, and serious poisoning can result from less than two weeks’ exposure.
The symptoms include tremors, clumsiness, personality changes, memory problems, and emotional instability. (You know the phrase “mad as a hatter”? Hatters used mercuric nitrate in making felt for the hats, and their chronic occupational exposure left them, well, mad.)
I was reading through the tox literature on mercury poisoning this morning. I was actually trying to find a specific case that I remember from a few years ago where two boys had broken something (I think it was a sphygmomanometer) in their bedroom and hidden it from their parents. Both boys were hospitalized with neurological problems and the younger brother did die. I couldn’t find that specific case. I was surprised, though, that a lot of the reported poisonings aren’t from accidents with mercury-containing items, but from people trying to refine gold or extract silver from old dental amalgam in their kitchens. Home smelting, who’d have thunk it?
Even more interesting (in a I-never-would-have-thought-of-this way) is the exposure from certain religious rituals. Apparently mercury is sold as “azogue” and is sprinkled around the house or burned in candles (which is a great way to vaporize it) in Esperitismo, Santeria, and Voodoo. (I don’t know much, I admit, about any of them. They kinda scare me, and they scared me before I found out they were into mercury poisoning.)
There was some discussion on a safety mailing list to which I belong about how we all, as kids, used to play with mercury. Being chemists, lab safety officers, industrial hygienists, etc., nobody thinks that the remediation efforts in DC are overkill, and nobody is giving their kids a handful of mercury to play with now. But in trading stories we did find that our youthful exposure was not insignificant, leading several people to formulate the same hypothesis:
Mercury exposure causes normal people to become safety professionals.
After all, there has to be some explanation...
Posted by Nic at October 8, 2003 12:19 PM | TrackBack