Poisoned coffee sent six Harvard Medical School researchers to the hospital last August with symptoms ranging from ear ringing to fainting. HMS waited until last Friday to let people know that the incident occurred, and in the memo that they released, they told us the name of the semi-deadly chemical that caused the calamity: sodium azide.

There's more info about the incident in today's copy of The Crimson, but if you want to know more about NaN3 and about the mystery, check out what we've discovered below.

The funny thing about sodium azide is that it usually saves lives. That's because, according to the Centers for Disease Control and Prevention, sodium azide is best known for its role in air bags. When a car crashes, an electric charge causes the sodium azide to explode and, in turn, release nitrogen to inflate the air bag.

In this case, though, sodium azide almost did the opposite. When consumed, inhaled, or touched, it's said to have symptoms similar to cyanide: rapid breathing, dizziness, and an increased heart rate.

These symptoms prompted the six to rush to Beth Israel Deaconness Medical Center (one in an ambulance, according to Mabel P. Duyao, research director in the HMS Pathology Department) on August 26. The Harvard University Police Department is in the process of figuring out how the sodium azide got into the coffee machine, but as of now, what happened is still a mystery.