What is pollution?

• A. The introduction of contaminants that cause adverse change.
• B. The absence of any contaminants.
• C. The emission of only greenhouse gases.
• D. The process of cleaning up contaminants.

Answer: (B)

Pollution is the introduction of contaminants into the environment at levels that cause adverse changes to air, water, soil, or living organisms. This definition captures the harmful impact that contaminants—whether chemicals, biologicals, or particulates—can have on health and ecosystems.

The idea of no contaminants describes a clean environment, which is the opposite of pollution. Pollution isn’t limited to greenhouse gases; it includes many types of pollutants, not just those gases. Finally, the process of cleaning up contaminants refers to remediation, not pollution itself.