Yuck! This coffee tastes like poison!

Medical institutions in the US northeast have always been competitive, and Harvard has always been toward the top of the list in that category. I don't mean just competitive to get into. I mean competitive, period. I went to another big research medical school in the northeast in the sixties and we used to joke that at Harvard if someone put on his dorm light (it was pretty male in those days) in the middle of the night to go to the bathroom, all the other lights on the floor would go on, too, on the theory someone was getting ahead of them. Put that down to prestige envy, perhaps, but as a resident of the northeast I can attest that the whole region is a pressure cooker, even more so for academics. Whenever we travel to other parts of the country it takes us a couple of weeks to decompress, and then we marvel at how much slower -- read that saner -- the pace of life is elsewhere. I mention this because it was the first thing that crossed my mind when I read in Nature magazine's blog, The Great Beyond, about what looks to be the intentional poisoning of six Harvard researchers via the water reservoir in a single-serve espresso machine. The agent was a common preservative found in many labs, sodium azide:

When Lidia Bosurgi, a 25-year-old Harvard Medical School doctoral student from Italy, took a sip of coffee Aug. 26 during a research break, she immediately knew something was strange.

First, she noticed the java tasted odd, then she felt burning in her throat and her ears began ringing.

“I had just a sip of the coffee and my blood pressure went down and I had all the symptoms that I was fainting,” she said in a Herald interview two weeks ago.

It wasn’t until weeks later that she would learn the cause of her symptoms: sodium azide, a toxin often compared with cyanide and commonly used in medical laboratories as a preservative.

Bosurgi, who declined to speak to the Herald when called back yesterday for a follow-up interview, was one of six researchers, students and doctors who fell ill in Harvard’s pathology department after drinking from the same coffee machine that day. She and her colleagues were all sent to the emergency room, at least one stayed overnight after passing out.(Boston Herald)

Yikes. So what is sodium azide? It's a pretty simple molecule, formula NaN₃ and has some amusing properties other than being a novel way to flavor coffee. Contact with metal makes it explode (not a good thing to dump down the drain), as does heating it to 300 degrees C. The latter property is used in your car to make the airbags inflate -- explosively. When you hit something it triggers an igniter and the sudden conversion of those three nitrogens in the salt to nitrogen gas inflates the airbag in 50 milliseconds. Outside of airbags, it is usually found in the form of easily dissolved white crystals. Its poisonous properties come from its ability to knock out cytochrome c oxidase by binding competitively to its heme moietie like carbon monoxide or cyanide. Cytochrome c oxidase is the last step in the mitochondrion's bucket brigade system of transferring an electron from a food to the final acceptor, oxygen. When you knock out cytochrome oxidase, in essence the cell asphyxiates even though there is plenty of oxygen. It affects human cells that way, but also bacteria and fungi, so it is used in laboratories as a biocide in reagents and stock solutions to prevent growth of gram-negative bacteria. It's also used for pest control in agriculture.

So how did it get in the coffee?

A Harvard Medical School spokesman says university police are trying to determine whether the coffee was intentionally or accidentally tainted.

David Benjamin, PhD, a Chestnut Hill toxicologist, says it appears to him to have been intentional. "You would have to take the chemical and add the chemical to the reservoir in the coffee maker," says Benjamin who consults in legal cases. "It's a remote possibility that it's accidental," he says. (WBZ-TV, Boston)

Remote or not, it could have been an accident. If it was in the water reservoir, the most likely way for this to happen was that a container that had sodium azide residue or a small amount of stock solution in it was used to fill the reservoir with water. Possible. But now the going theory is that it was foul play. Perhaps it was an attack on someone known to use the common room's coffee machine. Or some malicious attack on the lab or the institution.

Or maybe just another way to gain that ever important competitive edge.