``gamma``-Butyrolactone (γ-butyrolactone or GBL) is a hygroscopic colorless liquid with a weak characteristic odor which is soluble in water. GBL is a common solvent and reagent in chemistry as well as being used as a flavouring, as a cleaning solvent, as a superglue remover, and as a solvent in some wet aluminium electrolytic capacitors. In ...