Diethylene glycol is an organic compound with the formula (HOCH₂CH₂)₂O. It is a colorless, practically odorless, and hygroscopic liquid with a sweetish taste. It is a four carbon dimer of ethylene glycol. It is miscible in water, alcohol, ether, acetone, and ethylene glycol. DEG is a widely used solvent. It can be a normal ingredient in various consumer products, and it can be a contaminant. From Wikipedia