Originally Posted by p.giannakis
I have to say that i am no expert in chemistry - but my wife is.
According to her, oxidation does not need oxygen in order to take place. It doesn't need water either. If chemicals react between them and one absorbes electrons as a result of the reaction, that element is 'oxidised'.
That's my 2 cents.
There's an interesting thread over at apug where this, or something like it, appears to be occurring in Pyrocat that is mixed in glycol without water. When the glycol versions were announced it was thought that that they would offer much longer shelf life (and it seems that they do) but they can still deteriorate. I don't know if that's because after repeated opening of the bottle some water from the air is gradually introduced, or, as been suggested, there is actually a reaction taking place which is not primarily about water.