Get the mercury out! It just doesn’t sound the same as “get the lead” out does it? But lead and mercury are both heavy metals. They are about the same molecular mass, both grey in color, both widespread in the earth’s crust, both widely used in industrial applications in the past, and both neurotoxins. But one is a solid at room temperature and the other is a liquid.  An engineer told me he didn’t know why I was spending so much time on getting mercury out of the water, because he’d played with it all the time when he was a kid. He’d rolled it over his hands and arms, polished up silver dimes with it, and generally considered that he had no ill effects as a result.

Little did my friend the engineer know (and I don’t know why he never took any chemistry) but mercury volatilizes at room temperature. So he was breathing mercury vapor. Probably not for very long, but still he was getting exposure. I don’t know what the effects of rubbing it all over your skin are, so I checked out the ATSDR fact sheet. ATSDR is the Agency for Toxic Substance and Disease Registry. It is part of the Communicable Disease Center (CDC for short). ATSDR is the environmental health organization. If you want to know something about the effects of a chemical on your health, they are your source. So I checked out the fact sheet and it says generally there is no absorption through unbroken skin.  However, I am not going to recommend that you take up rubbing mercury around on your skin.

I did get a look at what happens to you if you do get seriously exposed to mercury vapor; what they call acute exposure. This would be like in a major industrial setting I expect. Symptoms are corrosive bronchitis with fever and chills, abdominal cramps, diarrhea, central nervous system damage leading to neuropsychiatric disturbances and tremors. Oh and kidney failure, respiratory failure, and death too. Then I took a look at what the chronic effects are. That would be repeated or continuous exposure to breathing low levels of mercury vapors: tremors, anxiety, forgetfulness, insomnia, anorexia, excitement, drooling, fatigue, cognitive and motor dysfunction, muscle atrophy, hyperactive tendon reflexes, irritability, sleeplessness, sweating, severe leg cramps, and a painful peeling rash. Whoa! Sounds like zombie disease doesn’t it?

Anyway, I told my friend the engineer that I wasn’t worried about elemental mercury (the silver liquid) so much, since what we generally are concerned about in the water environment are compounds of mercury. Mercury forms all sorts of compounds with sulfur, oxygen, and chlorine. But the big concern in water is mercury also combines with carbon through a biotic process and produces methylmercury. Methylmercury is a neurotoxin. To tell you the truth I don’t know much about environmental health. Not my area, so I had to go back to ATSDR’s publications to find out what happens when you have too much methylmercury in your diet. They cited the classic case of Minamata Bay in Japan. This is a very sad story. And I’ll write about it in my next post.