The diethylene glycol contamination problem
Since 2022 WHO has issued a series of alerts on syrups and other oral liquid medicines contaminated with diethylene glycol or ethylene glycol, industrial solvents that can be fatal in small amounts. WHO links the problem to excipients and has asked manufacturers to test raw materials.
- WHO describes diethylene glycol and ethylene glycol as toxic chemicals used as industrial solvents and antifreeze agents that can be fatal even taken in small amounts, and says they should never be found in medicines.1
- On 23 January 2023 WHO reported cases from at least seven countries and more than 300 fatalities in three of them, mostly children under five.1
- WHO alerts in 2022 covered contaminated paediatric medicines identified in The Gambia and Indonesia.2,3
- WHO has asked manufacturers to test liquid dosage forms and excipients such as propylene glycol, polyethylene glycol, sorbitol and glycerin for ethylene glycol and diethylene glycol.3
- In April 2024 WHO reported falsified propylene glycol labelled as made by DOW in Pakistan, with ethylene glycol contamination ranging from 0.76% to 100%. DOW said the materials were not manufactured or supplied by DOW.4
- WHO said gas chromatography is a suitable and widely used test. Where it is not available, WHO said the International Pharmacopoeia suggests a thin layer chromatography screen first, with confirmation by gas chromatography.4
- In October 2025 WHO issued an alert after India's regulator reported diethylene glycol in at least three oral liquid medicines linked to child fatalities.5
- WHO asked manufacturers to buy excipients only from qualified suppliers and test materials on receipt and before use.1
Sources
- World Health Organization, WHO urges action to protect children from contaminated medicines (23 January 2023)
- World Health Organization, Medical Product Alert N°6/2022: Substandard (contaminated) paediatric medicines (5 October 2022)
- World Health Organization, Medical Product Alert N°7/2022: Substandard (contaminated) paediatric liquid dosage medicines (2 November 2022)
- World Health Organization, Medical Product Alert N°1/2024: Falsified (contaminated) USP/EP PROPYLENE GLYCOL (15 April 2024)
- World Health Organization, Medical Product Alert N°5/2025: Substandard (contaminated) oral liquid medicines (13 October 2025)