"Toxic" is not a physical or chemical property itself. It's a biological property that describes a substance's ability to cause harm to living organisms.

Here's why:

* Physical properties are characteristics that can be observed or measured without changing the substance's chemical composition. Examples include color, density, melting point, and boiling point.

* Chemical properties describe how a substance reacts with other substances. Examples include flammability, acidity, and reactivity.

Toxicity is determined by the interaction of a substance with a living organism, leading to harmful effects. This interaction involves complex biological processes and can vary depending on the organism, dosage, and exposure route.

Therefore, toxicity is not a property of the substance itself, but rather a measure of its potential to cause harm when interacting with a living organism.