How is propylene glycol antifreeze characterized compared to ethylene glycol antifreeze?

Propylene glycol antifreeze is characterized as being less harmful and generally safer compared to ethylene glycol antifreeze. This attribute makes it a preferred choice for applications where there is a potential for accidental ingestion by pets and wildlife. Propylene glycol is classified as "generally recognized as safe" (GRAS) by the FDA, which means it poses a lower risk of toxicity than ethylene glycol, which is toxic to both humans and animals.

While propylene glycol can still be harmful in large quantities, it is considered not dangerous in small amounts, particularly in household applications such as in food processing and pharmaceuticals. This safety profile contrasts sharply with ethylene glycol, which is highly toxic and a significant risk to animal health. Therefore, labeling propylene glycol as "considered not dangerous" accurately reflects its comparatively benign nature in both environmental and clinical contexts.

The other options are misleading, as propylene glycol isn't more toxic than ethylene glycol, doesn't have a classification that suggests harm to animals comparable to ethylene glycol, and it is not exclusive to electric vehicles; it can be utilized in a variety of cooling and antifreeze applications across different vehicle types.