How is a biohazard defined?

A biohazard is defined as a material of biological composition, especially if it is infective, that poses a threat to people or their environment. This definition encompasses a wide range of biologically-based threats, including viruses, bacteria, fungi, and other microorganisms that can cause diseases or harm to humans, animals, or ecosystems.

The key aspect of this definition is the focus on materials that are biological in nature and have the potential to cause infection or harm. This aligns with the general understanding of biohazards in laboratory and safety settings, where proper handling and disposal of these materials are crucial for public health and safety.

The other options propose definitions that do not capture the specific aspects of biological materials or mistakenly broaden the scope. For instance, defining a biohazard simply as any material that negatively impacts a biological organism neglects the critical importance of infectivity and threat level. Similarly, describing it as a chemical or limiting it to viruses fails to encompass the diverse range of biological agents that can be classified as biohazards. Thus, the chosen definition provides the most accurate understanding of what constitutes a biohazard in health and safety contexts.