The USFS tests fire retardants for mammalian toxicity, including oral toxicity, dermal toxicity, eye irritation and skin irritation.

The pet-friendly organization SafePaw, which produces “safe products for people, pets, property, and planet,” says that magnesium chloride ice melt is dangerous to pets. In a post on the company blog, they say, “Simply walking on an area that has been salted, exposes them to all the above magnesium chloride side effects [eye irritation and burn from contact, skin irritation and burn, metal fume fever, gastrointestinal irritation, respiratory irritation]. The salt will contact the skin on their paws. If they scratch or rub their face, it will get in their eyes. Animals like the taste of salt, and if they ingest it, an illness will result. Extreme exposure is fatal. The magnesium chloride brine also has side effects on pets.”