Despite the discovery of DEG’s toxicity in 1937 and its involvement in mass poisonings around the world, the information available regarding human toxicity is limited. Some authors suggest that minimum toxic dose is estimated at 0.14 mg/kg of body weight and lethal dose between 1 and 1.63 g/kg of body weight, while some suggest that the LD50 in adults is of ~1 mL/kg, and other suggest that this is the LD30. Because of its adverse effects on humans, diethylene glycol is not allowed for use in food and drugs. The U.S. Code of Federal Regulations allows no more than 0.2% of diethylene glycol in polyethylene glycol when the latter is used as a food additive.
Diethylene glycol has moderate acute toxicity in animal experiments. The LD50 for small mammals has been tested at between 2 and 25 g/kg, less toxic than its relative ethylene glycol but still capable of causing toxicity in humans. It appears diethylene glycol is more hazardous to humans than implied by oral toxicity data in laboratory animals.