Mystery Chemicals

So, suppose you are tidying up your laboratory for, let us say organometallic chemistry, and among the other things you encounter a decades-old brown glass bottle of— you have no idea because the label, if there ever was one, has come off, and of course no one remembers what is in there.

What do you do? You can’t just pour it down the sink. What is the protocol for dealing with unknown chemicals?

That’s an expensive situation. It has to be identified to know how to dispose of it and outside analysis can cost hundreds of dollars. That’s what universities do, however I suspect a lot of “educated guesses” are made so they can be labeled and disposed without outside analysis.

Didn’t you have qualitative analysis in high school chemistry?


I’m not sure if this is a joke, but high school chemistry scarcely enables someone to identify organometallic compounds. Either way, this isn’t appropriate as the second answer in GQ.

General Questions Moderator

In every lab I’ve worked in, I would have been required to report the mystery jug to the environmental health and safety people, who would have charged my lab a hefty fee for analysis and disposal.

Here’s a random university link addressing the issue, including a form for analysis of unknown material. Unknown Chemical Waste Disposal | Campus Operations

ETA mod already dealt with it.

If it’s a brown bottle then I expect it’s some kind of semivolatile organic, and there would be a waste vessel for that. I could do a sniff test to confirm. It might also have toxic metals, and in that case I’d send it to the metals dept to check for mercury or anything that shouldn’t go into SVO waste.

But really, this kind of situation would never happen anywhere I ever worked. Putting unmarked containers on the shelf was considered a disciplinary offence. I would think this kind of scenario would only come up in surreptitious drug or weapons labs, where law enforcement would have robust resources to process that sort of thing.

So, assuming you weren’t breaking any laws by possessing whatever the chemical is, you can contact your local fire department. That department, or some fire department or agency they know of, has a plan for unknown chemical removal. Even if you haven’t broken the law by possessing this chemical you still might be liable for a clean up cost.

Some organometallics have explosive reactions with water or other chemicals. I would take personnel safety first and consult the fire department for disposal.

Suppose such a bottle is found somewhere in a lab that does diverse work with a very wide range of dangerous chemicals, and it could be virtually anything. How would the analysis begin to narrow it down?

If it had a potential to be explosive, then the safest way is to dispose it like IED or Bombs are disposed.

If it is not, and is suspected to be organic : then a FTIR usually yields good results.

If it’s inorganic : Thermo gravimetric analysis

If it’s a solid : Electron Microscopy

I am a Chemical Engineer and the above is based on my limited experience of finding stuff in chemical plants. A chemist can correct me and provide more detailed flowchart.

I was thinking about this, but this would work only if you were sure that the only risk was detonation. Is there some way to carry out a controlled detonation in a manner that would not spread it everywhere?

Maybe you first take a very small sample and do a test detonation?

Or in any number of university labs. They can be scary places.

There are things that shouldn’t happen…but when they do there has to be a way of handling them. In short, there are companies that will dispose of such chemicals, but at a steep price.

Some decades back I worked in the chemical stockroom at a research site for “Big Pharma”. Our stockroom had not only standard stock reagents, but we stored all of the thousands of little 10ml bottles of Aldrich chemicals that the scientists used in their labs. They would order five bottles of 1,2,3,4,somethingorother and use two and a half. They would then tape them with Parafilm and turn them in to us, at which point we would catalog them, put a stock number on them, and store them on our shelves for others to use. We functioned exactly like a university library with “closed stacks”–people would come to the counter with a wish list and we would find the items for them and check them out.

We had tens of thousands of bottles of diverse organic compounds on our shelves. The air had a pungent aroma. My liver still feels ticklish to this day.

Over the years, many of the bottles would leak, or they might have come in contact with corrosive stuff in the laboratories, or neighboring bottles might have leaked. As a result we had many bottles with illegible labels. This is one perfectly proper reason why there might be unlabeled bottles. Sure, the storage should have been monitored more closely, and they shouldn’t have had gunk sprayed on them in labs, but tell that to several hundred chemists who are checking in and checking out chemicals.

In a prior corporate acquisition, we ended up receiving several cases of random chemicals that had been all sealed up, packed in sawdust or vermiculite, and shipped to us. These remained on our back shelves for a few years, unopened.

Finally, in an era before major computerization, or in smaller labs, the catalog system might be on file cards–definitely not something that would survive the transfer from one organization to the next–so even the old shelf stock number was usually useless if the main label had been defaced.

Eventually we contracted a disposal company to take all of those cases, along with many chemicals that were too sketchy to keep on our shelves. I don’t know exactly what they did with them, but I believe that most were incinerated. They charged quite a bit for the disposal.

I am not an explosives or chemistry expert, but per my understanding some organometallics have the potential of exploding in the very act of sampling.

For example, when we learnt about chemical production in college, there was the case of Nitroglycerin manufacture. What we learnt was that NG was never pumped (it explodes) but was produced on top of a hill and allowed to flow down pipes under gravity. Pipes had explosion catching stations and different units were separated by hills and valleys. The hills provide natural explosion barriers.

Sudden acceleration in a pipe or a sampling syringe can set it off.

Check out this thread from In the Pipeline

There will probably be similar threads there; browse through:

Yes and you might be dead. Just because the lab specializes in organometals does not imply that that is what is in the bottle.

When I was working in a lab many years ago, we came on an unlabeled bottle in a chemical cabinet. Two clues: the bottle was wax and tightly sealed. Nonetheless the glass front of the cabinet was highly etched. There was nothing else in the cabinet that could cause that, so we quickly worked out what it was (H2Fl2). I no longer recall how we disposed of it, but no one sniffed it.

Now that is an enlightening, and hair-raising thread:

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.

I’m pretty sure it’s still there as everyone thought it better to just pretend the bottle didn’t exist.

The real life protocol (as opposed to the official one) is to leave the unknown chemical in place until it becomes somebody else’s problem. In fact, that’s the official protocol for spent nuclear fuel.

There’s no risk in doing a wafting odor test in a general lab, assuming you’re following standard safety procedures.

You can’t really rely on an unlabeled bottle as much of a clue, but a brown bottle would suggest to me that it’s organic and/or light sensitive.

If nothing else, there’s the risk that it might react energetically on contact with air. You can’t waft it without opening it.

And the brown bottle could mean that it’s light sensitive, or it could mean that it’s so old that it dates back to when brown glass was cheaper.