What concept identify the four routes of entry for toxic substance into body?

The four routes of entry for toxic substances into the body are:

1. Inhalation: this is the most common route of entry for toxic substances, and occurs when substances are breathed in through the nose or mouth. This can include dust, fumes, gases, vapors, and aerosols.

2. Ingestion: this occurs when substances are swallowed, either intentionally or unintentionally. This can include food, drink, or other objects that contain toxic substances.

3. Dermal absorption: this occurs when substances come into contact with the skin and are absorbed through the skin. This can include liquids, solids, or gases.

4. Injection: this occurs when substances are injected into the body, either intentionally or unintentionally. This can include injections from medical procedures, insect bites, or accidental punctures.