Sciencemadness Discussion Board

Toluene escaped the bottle - what is the risk?

Murexide - 1-4-2020 at 21:29

Hello,

Having left a purchased and enclosed 1L plastic bottle (plastic seal, original packaging and unopened) of toluene outside about 6 months ago, I came back to check on it today and discovered That 90% of the toluene had escaped the bottle, with the bottle compressed but no leakage! There was a fairly strong smell of toluene in the vicinity, but at undetecrable to fairly low levels inside.

First, what sort of risk does toluene pose at this concentration?

Second, is this a common experience among amateur chemists?

[Edited on 2-4-2020 by Murexide]

[Edited on 2-4-2020 by Murexide]

draculic acid69 - 1-4-2020 at 22:14

Is it common, nope.toluene usually behaves well and stays put. A coke bottle is fine for toluene and will not leak.itll last year's in a coke bottle.

Murexide - 1-4-2020 at 22:38

Might have something to do with the large and possibly loose cap. Now that I do recall, the bottle may not have been upright for a prolonged period

How dangerous is 6 months exposure to toluene at fairly low (barely detectable) concentrations though? I've heard it's not substantially toxic or carcinogenic, which is good.

Fery - 1-4-2020 at 23:42

Exposition was at very low concentration, so the risk was negligible. Poor people in my country used to sniff toluene thus they damaged their brains (dementia) after very long time (years) and their exposure was at very high concentrations (their bodies released such amounts of toluene that anybody else could smell it).
I've bought 1 L of toluene 1 year ago and it came in a plastic bottle and the lid was tightly closed (I always check that) and the flask was stored in upright position but after 1 week I saw that about 50 ml leaked. So I poured the toluene into glass bottle and used the same cap to stopper the flask and then no leakage anymore. I even usually wrap few layers of teflon tape to the gap between the lid and the neck of flask. Sometimes I put a container into bigger one (e.g. Hg, Br2) or into plastic bag (very hygroscopic chemicals like P2O5 etc), but that's another story (preventing anything to enter the container from outside).

[Edited on 2-4-2020 by Fery]

Refinery - 4-5-2020 at 00:12

I checked through my inventory recently and found several years old toluene bottle that was still factory sealed. I found it oddly light, and only found out that 70% of the contents were evaporated. The lid was made out of PE plastic, the rest of the can being steel.

So they do not last forever, at least in such packings.

mackolol - 4-5-2020 at 01:07

Evaporation of stored toluene is nothing in comparison do DCM or acetone. I have big problem in storing them as they escape...

G-Coupled - 4-5-2020 at 01:08

Can confirm, Toluene (and Xylene) like to escape from the plastic bottles they tend to often be sold in. Decanting them into orange glass bottles with plastic caps seemed to prevent this from happening.

Also, keeping them refrigerated appears to help - stopping the bottles from 'burping' when opened, presumably from having lower vapor pressure inside.

mayko - 4-5-2020 at 10:53

Worrisome, but my #1 concern would be fire/explosion hazard should the vapor hit an ignition source, rather than toxicity.

G-Coupled - 4-5-2020 at 11:08

Quote: Originally posted by mayko  
Worrisome, but my #1 concern would be fire/explosion hazard should the vapor hit an ignition source, rather than toxicity.


Not terribly likely at the (relatively) very slow rates at which the vapors escape, I'd have thought. They're not *that* flammable.

Refinery - 5-5-2020 at 00:48

Highly unlikely it will reach LEL anytime.

Copenhagen1968 - 5-5-2020 at 01:10

Plastic bottles are barriers to liquids but not vapours.
The permeability depends on the polymer type.
Plastic bottles can conveniently be regarded as a tight mesh of polymer chains and as such are not impermeable to gases.
A known example is a bottle of household vinegar. The liquid evaporates steadily through the plastic, while the bottle squashes owing to the volume decreasing.

DavidJR - 5-5-2020 at 01:35

Yeah, use glass bottles where possible

Refinery - 5-5-2020 at 03:32

I would think that if leaching through plastic cap is an issue with glass bottle, you could cut a piece of al foil between the cap and the bottle, because metal is impermeable in this matter.