In the context of biosafety, what is a biological agent?

A biological agent refers specifically to a microorganism (which can include bacteria, viruses, fungi, and parasites) or a toxin produced by such organisms that has the potential to pose a risk to human, animal, or plant health. In the field of biosafety, understanding the nature of biological agents is crucial as they can lead to infections, diseases, or other health-related issues if not managed properly. This definition encompasses not only pathogens but also substances that can affect health adversely.

In contrast, the other choices do not align with the definition of a biological agent. Harmful chemicals, while they can pose risks in a laboratory, fall under the category of chemical agents rather than biological. Mechanical devices for filtering air are related to safety equipment but do not constitute biological agents themselves. Similarly, waste disposal systems deal with the management of materials, including biological agents, but they are not classified as biological agents.