[lagolinguini]

I think the subtle difference is that alcohol not for human consumption must be denatured, and can be synthesised.

[sidewndr46]

No, that's the point. You can't use denatured alcohol in a lab. It has to be nearly pure ethanol, with some percentage of water.

[nanidin]

My chemistry professors told us that if someone tried to drink the ethanol in the lab their throat would seal off and they would start to choke because it will suck the moisture out of your tissue due to it being nearly anhydrous.