Disposal of Used Antifreeze

Many vehicle maintenance operations generate used antifreeze. Before use, antifreeze is not considered a hazardous waste. However, after antifreeze goes through a radiator it may become contaminated by fuel, oils and metals. Many of these contaminants, particularly metals and benzene, are toxic and may cause the used antifreeze to exceed one of the hazardous waste definitions thresholds.

Antifreeze would be considered hazardous if it were mixed with a hazardous waste such as solvent or gasoline. Antifreeze could also be hazardous if has picked up enough metals to be characterized as hazardous for metals content (>5 ppm lead for example) or if the pH > 12.5. Have your antifreeze tested for the hazardous waste characteristics if you are unsure of the waste antifreeze characteristics.

For more information, visit EPA's Antifreeze Web site.