Agency for Toxic Substances and Disease Registry
Case Studies in Environmental Medicine (CSEM) 

Ethylene Glycol and Propylene Glycol Toxicity
Where Is Ethylene Glycol Found?

Learning Objectives

Upon completion of this section, you should be able to

• identify sources of ethylene glycol exposure.

Introduction

The most common source of ethylene glycol exposure is antifreeze, which can contain up to 95% ethylene glycol. Antifreeze is readily available at hardware and automotive stores.

Waste streams produced from the manufacture or use of ethylene glycol account for the most significant releases of this compound into the environment.

Commercial Products

Commercial products* containing high concentrations of ethylene glycol include

• Dowtherm SR1
• Lutrol-9
• Norkool
• Tescol
• UCAR-17

^*Use of trade names is for identification only and does not imply endorsement by the Public Health Service or the U.S. Department of Health and Human Services.

Environmental Exposures

Waste streams produced when ethylene glycol is manufactured or used account for the most significant releases of this compound into environment. In military and commercial aviation, large amounts of ethylene glycol are used for de-icing. It is sprayed as an aerosol or mist onto airplane wings to prevent ice buildup. Used in this manner, ethylene glycol may contaminate groundwater near airports through runoff and may expose workers to air levels ranging from (mg/m³) to 10.4 mg/m³ (i.e., <0.02 parts per million [ppm] to 4.2 ppm)

Occupational Exposures

People who work in industries that use ethylene glycol may be exposed by touching these products or inhaling mists from spraying them. According to the guidelines set by the American Conference of Governmental Industrial Hygienists (ACGIH), the ceiling limit of ethylene glycol in workplace air is 39.4 ppm. (American Conference of Governmental Industrial Hygienists. 2003) Except for operations where ethylene glycol has been sprayed or made into a mist or vapor, exposure to it in the air is unlikely (Agency for Toxic Substances and Disease Registry 1997).

Ethylene glycol is used in spacecraft coolant loops and in aviator protective clothing. Both applications present potential for exposure if leaks occur.

Key Points

• Antifreeze, which typically consists of 95% ethylene glycol, accounts for about 40% of the ethylene glycol produced and is easily accessible to the general public.

Progress Check