What is a characteristic of a substance defined as a pollutant?

A characteristic of a substance defined as a pollutant is that it primarily affects visual and aesthetic aspects. Pollutants are often identified by their negative impact on the quality of the environment, including water, air, and soil. They may introduce substances that can make a natural resource visually unpleasant or harmful to health. For instance, excess nutrients can lead to algal blooms that change the water's appearance and can also produce odors or toxins.

While a pollutant may have aesthetic impacts, such as discoloration or bad smells, it is essential to recognize that pollutants inherently possess qualities that can adversely affect ecosystems and human health, not just appearances. Therefore, focusing on the visual and aesthetic aspects highlights the broad implications pollutants can have beyond just physical presence, reinforcing the need for effective management and mitigation strategies.