Back to science! I will admit that my Twitter feed is going to be rather more politicized than usual for some time to come, but this is not a political site, and thank God for that. I have to say, it certainly brings in the comments and the traffic, but that’s not my goal in life.
A reader sent along a query that’s about as far from current events as possible, and I think that a lot of us are in the mood for some of that. It’s about storing reagents. I know that a lot of labs, and even whole departments, especially in academia, often just go straight alphabetical. The question was not so much whether that makes sense or not, but whether or not it can lead to very incompatible things being crammed in right next to each other.
I think that a lot of places use a “modified alphabetical” system, though, where the run of normal-ish reagents are stored by name, and more reactive stuff is moved out over to the side. Strong acids, strong bases, reactive gases – these traditionally have their own storage cabinets anyway, and there are also places that separate out strong oxidizers and/or strong reducing agents as well. Then you have the whole room temperature versus fridge versus freezer storage issue as well, which also tends to separate out the more reactive stuff into the colder compartments. (In my own experience, it’s cold storage in the labs, which is definitely necessary, that does more than anything else to randomize the attempts to track reagents department-wide).
Individuals and individual labs, naturally, sometimes evolve their own systems. From an organic chemistry viewpoint, there’s a lot to be said for a whole cabinet that’s nothing but primary and secondary amines, for example, or a whole box of isocyanates or carboxylic acids. Synthon-based storage tends to get hard to manage after a while, especially with multiple functional groups, but it can be very convenient. And since it’s based on chemical reactivity right from the start, it tends to get around the incompatible storage problem by definition. This is how things tend to get sorted out under my own hood, on a project-by-project basis.
If you have a completely bar-coded system, though, which you really need to if you’re actually going to be able to track everything, then you don’t have to store alphabetically at all, or by any system other than something tied to the number on the bottle. Organizing them by bar-code would work fine, except you’re almost certainly going to have things that shouldn’t be sitting next to each other, so the sort-out-the-reactives techniques mentioned above are usually employed. That way, when you search for some reagent, its location comes back first as “Acid shelf”, “Oxidizer cabinet” or whatever.
That’s only going to work, though, if people actually put the flippin’ bottles back in the right flippin’ places, and there you have the weak link of every single reagent storage system: the flippin’ chemists. We suck at this. Everybody’s just going to borrow the bottle of the ortho-fluoro intermediate for just a few minutes and then bring it right back. Well, tomorrow, definitely tomorrow. Maybe Monday – I had to set up the reaction again to make more. And so on. No one ever gets around to noting exactly which chemicals are wandering around like this, no matter how many scanners you install or how spiffy the software might be. The only solution I’ve seen, and I’ve seen it implemented many times, is a periodic scan-down of everyone’s bench, hood, and fridge to locate where everything actually is, for at least a little while, as opposed to who had it three months ago. This works pretty well, but it also means that you have to have a staff that does nothing else, which is hard to arrange in many academic departments – the time-is-money attitude in the company labs ensures that people are hired to do just that job, though.
So here’s a question to finish off with: what’s the worst/stupidest/most potentially catastrophic chemical storage you’ve had the displeasure of seeing? I think my own might have been when I came across about half a kilo of chromium trioxide baking in an open dish in a drying oven, the same one that people dumped solvent-soaked glassware into regularly. Or maybe it was the moment during my first year of grad school, studying at a little cubicle in an unused lab, and looking up to see that there was an old kilo jar of benzidine next to my head. No, scratch that one, at least it was in a sealed container. The worst I can think of at the moment happened to a colleague of mine years ago in a biology department. A notice had come out to everyone about old peroxide-forming reagents needing to be disposed of, especially in the non-chemistry labs. The biology lab head involved read this, noted the part about possible crystalline peroxide formation, went over to a cabinet and rummaged around for an elderly can of diethyl ether in the far back corner, and then shook it next to their ear to see if it sounded like had deposited any solid. My colleague who witnessed this bold analytical technique reported to me that it was the first time they’d ever felt the hairs on their head actually lifting up in panic, and also reported that they never wanted to experience that sensation again, if that could be arranged.
Update: I’ve heard from my source for this incident! Their comment was “You make me sound a lot more polite than I was at the time.” Much shouting and exchange of Anglo-Saxon vocabulary took place after the audiometric assay, as one can well understand.