What is a significant safety concern with ethylene glycol (EG) coolant?

Ethylene glycol (EG) coolant is primarily recognized as a significant safety concern because it is toxic to humans. Ingestion of ethylene glycol can lead to serious health issues, including kidney damage and central nervous system effects, and can be fatal in high doses. Its sweet taste might make it attractive to children and animals, increasing the risk of accidental poisoning. As a result, proper handling, storage, and disposal of EG coolant are critical to ensure safety in environments where it is used.

The other choices, while they may pertain to the properties of ethylene glycol, do not present the primary concern regarding health and safety. Understanding its toxicity emphasizes the importance of being cautious when working with or around this substance.