Friend or Foe: Deceptive Chemistry

Which of these two molecules looks more menacing–the one on the left, or the one on the right? To me, the one on the left is a sprawling creature, its “tentacles” branching out in all directions. The one on the right looks innocent–almost too simple to do any harm. But the fact of the matter is that while one of them will give you a headache, the other will relieve it: the one on the left is C₉H₈O₄–2-acetoxybenzoic acid–or, as most people call it, aspirin. The one on the right, however, is C₉H₈O and is known by its official name, 4-methylcyclohexane methanol (rolls right off the tongue), often abbreviated MCHM.

If the name 4-methylcyclohexane methanol rings a bell, that’s because it was the primary chemical involved in the recent chemical spill in West Virginia that left 300,000 people without safe drinking water beginning on January 9th. If it doesn’t sound familiar, that’s okay–most news agencies didn’t even attempt to have their news anchors attempt a pronunciation. (In fact, Stephen Colbert was the television report I saw that talked primarily about the chemical, even if it was in a rather satirical way–linked at the end of this post.) Even print and newspaper articles refrain from publishing its name, instead simply referring to it as “the chemical.”

So what what’s with MCHM’s big official name? And what does it even do? The name 4-methylcyclohexane methanol has a few different “parts,” so we’ll (briefly) tackle them one by one. The “hexane” part simply refers to a hydrocarbon with 6 carbon molecules (a hydrocarbon is a molecule comprise of only hydrogen and carbon). Not bad so far! The “cyclo” prefix means that the molecule is orientated in a ring. “Methyl” means that there is a methyl (CH₃) group attached to the molecule, and the 4- tells you where it’s located on the molecule (at the bottom of the ring). And finally, the “methanol,” which is located at the top of the ring, means that there is a methanol (CH₃OH) attached to the central ring–the OH is highlighted in red.

That was a lot of words to describe such a simple, innocent-looking molecule. It would take even more explanation to describe the aspirin molecule. At a simple glance, there would appear to be similar parts in aspirin as MCHM–for example, there’s a ring and even an OH in the aspirin molecule. However, the ring is a completely different animal, and the OH, due to the combination of elements in the aspirin, also serves an entirely different purpose.

Anyway, what does MCHM actually do? Every news report I’ve seen simply labels it a coal “frothing agent.” But what in the world is a frothing agent, why does coal need to be frothed, and how do you even “froth” coal? It all stems from the fact that coal is mined from the ground, which means it’s dirty. It needs to be cleaned.

Underground Coal Mine

Surface Coal Mine

Well, not cleaned like you might dust the blinds. The cleaning process removes impurities from the coal that is dug out of the mine–rocks, minerals, and other contaminants. “Cleaner” coal is more valuable and burns better. However, while some of the impurities can be physically removed (kind of like dusting the blinds, actually), some of the contaminants need chemical assistance to be removed. From what I can understand of the limited information available on the process, the coal is crushed and then a sort of slurry is created of coal and a liquid. The MCHM “frothing agent” serves to aid in creating bubbles in the slurry, and the contaminants are attracted to the bubbles and are carried away from the coal. Freedom Industries manufactures MCHM, which explains why it was sitting in their tanks.

But how dangerous is it? While you wouldn’t really want to rub MCHM on your skin or ingest it, according to an article in Scientific American, it turns out MCHM actually is broken down naturally by microbes in water. This is good news–nature can actually take care of the spill itself in a matter of weeks (in addition to the human efforts to clean up the spill). The Scientific American article also notes that people are in general exposed to more harmful chemicals that MCHM on a daily basis–gasoline, for example. So while the spill needs to be dealt with, it is a bit less dangerous than the media would have you believe–and that is precisely what I’m going to address in my next civic issues post. The bad news is that earlier this weeks, newly released reports stated that a second chemical may have been involved in the spill. Regardless, for now, hundreds of thousands of West Virginians are still without safe drinking water.

The Colbert Report segment on the spill:

Sources:
http://www.scientificamerican.com/article/how-dangerous-is-the-chemical-spilled-in-west-virginia/
http://www.chemspider.com/Chemical-Structure.105625.html
http://en.wikipedia.org/wiki/4-Methylcyclohexanemethanol
http://en.wikipedia.org/wiki/Aspirin
http://www.nytimes.com/2014/01/23/us/a-second-chemical-was-part-of-west-virginia-chemical-spill-company-reveals.html