A former colleague was telling me the other day about some not-so-pleasant surprises that occurred when he was helping to clean out a lab that hadn’t had some cabinets opened in a while, and I think many readers will have had such experiences. Academic labs are particularly prone to Easter eggs of this sort, since there’s a continual turnover of lab occupants over the years, a number of common storage areas (some of them probably rather obscure), and a strong incentive for many of them to leave quickly on finishing their degrees without necessarily taking care of every single loose end.

Duke’s chemistry department (around the time I left) tried instituting a check-the-cabinets policy after someone had bequeathed to posterity a couple of liters of unused diazomethane/ether solution in a lab fridge, which I think was helpfully labeled with something like “Big batch”. This generous donation was not received well when it was finally discovered and identified, and the plan was to keep that sort of thing from happening again. I made it out the door myself under the inspection conditions (believe me, I was in a mood where nothing was going to stop me), but I wonder how long the system was kept up and how well it worked.

Industrial med-chem labs tend to be a little less lively for that kind of thing, for several reasons. We’re willing to spend more money, so there’s less of the well-I-guess-I-gotta-make-it-myself-might-as-well-make-a-pile attitude for weird reagents. And the occupants of the labs tend to hang around for much longer, which gives them less of an incentive to leave Superfund-level stuff piled up for the next wave of people to deal with. There are also the industrial health and safety people, who tend to be more vigorous (or perhaps less overwhelmed) than their academic counterparts. The worst experiences I had digging around in industry labs came in the early 1990s when my company packed up and moved the entire research site, vacating buildings that had been occupied for decades. All sorts of antique equipment came to light, and I recall finding an entire dropping mercury electrode setup from the early 1950s, still in its box with classic brush-script lettering and all – it was something like an “Electro-Matic”, and sure enough, there was still mercury in there when I opened it up. Probably hadn’t seen the light of day since the Eisenhower administration. Like most everyone else, I have at various times found plastic screw-cap bottles half-full of mercury (with gunk floating on top of it) stuck in the back of cabinet spaces, and all I can say is that at least they were closed.

Some of the other buried treasures I came across over my academic career, though, included an unused bench drawer, empty but for a bottle of what had at one point been freshly prepared solid sodium amide. It had gone orange on prolonged aging, which is not so good, because that stuff (some sort of mixture of oxides) can explode on you. There were always those sealed round-bottom flasks in the back corners of hoods, gradually accumulated a furry collar of dust, with (if you were lucky) an illegible fading label on them. Some of those things burst into flame when someone finally opens then, and some of them don’t – there’s only one way to find out.

When I first started graduate school, I was assigned a desk in a disused lab. One evening I idly started looking over the shelves and discovered that I’d been sitting right down the way from about a kilo of benzidine. It had, if I recall correctly, an ancient Eastman Chemical label on it – my maternal grandfather was an early employee of Tennessee Eastman in Kingsport, a town that was largely rebuilt for that company and whose unusual smells I recall from childhood visits, and I wondered if he’d been around when that one left the plant. Anyway, there are all sorts of things that people believe (wrongly) will give them cancer, but the case for benzidine exposure is unfortunately pretty solid, so I turned that one into problem for the waste disposal people as soon as possible. Duke’s old chemistry building had a lot of nonchemical oddities shoved into corners as well – the second-floor lab where I used to prepare levoglucosan had a bunch of old PDP-8 computing hardware scattered around it, which looked paleolithic even at the time, although it was only twenty years old.

There are others, but I’ll throw this one open to the readership: what’s the strangest (or most terrifying) thing you’ve come across in cleaning out an unused chemical space? Among the worst I’ve heard was a bottle of di-isopropyl ether that was forming beautiful crystals of the peroxide under its long-undisturbed surface, and I’m very glad that I wasn’t around for that one! But what else do you have?

I’ll forestall one classic answer – for historical reasons, an awful lot of old stockrooms in high schools, etc., turn up bottles of picric acid, which generally causes panic. Really old and poorly sealed bottles can indeed dry out, which makes the stuff more sensitive, but it’s also not the Instant Bomb of the popular imagination. Now, metal picrate salts (formed in old unexploded munitions, for example) are another matter, but those are a bit less common in high school closets. Definitely call someone to dispose of picric acid if you come across it, but don’t worry that you’re going to set it off as you tiptoe back out the door.