According to Paracelsus, what is toxicology?

Paracelsus, a Swiss physician and alchemist, is considered one of the founders of toxicology. He defined toxicology as the study of the adverse effects of chemicals on living organisms. He believed that "the dose makes the poison," meaning that any substance can be toxic if taken in a large enough quantity. This principle is still a fundamental concept in toxicology today.

To all things is a poison, nothing is without poison; only the dose makes a thing not a poison.