When consumed, ethylene glycol oxidizes and turns into glycolic acid. After this bodily reaction or process, it crystallizes in the kidney, causing eventual kidney failure. If inhaled, ethylene glycol can alter the delicate pH balance of the body, affecting the lungs, nervous system, and heart.
In animals, it attacks the kidneys and the nervous system in the same way; however, it takes an even smaller amount of toxin to be detrimental. Animals and young children are usually attracted to antifreeze due to its deceptively sweet taste.
The images to the left are of glycolic acid crystallized in a pig's kidney.
Below is the oxidation reaction for ethylene glycol, turning into glycolic acid.
The lethal dosages are as followed: two ounces can be fatal to a dog, one teaspoon can be lethal to a cat, and even two tablespoons can be hazardous to children. Along with the 45,000 hospitalizations over the past decade due to antifreeze poisoning, there are 10,000 - 90,000 animals harmed every year from ingesting antifreeze. It is important to note though that although every hospitalization does not end in death, and although it is impossible to distinguish the accidental ingestions from the malicious poisonings, as ingestion will lead to numerous problems afterwards, the usage and composition of antifreeze is an important matter of discussion and debate all the same.