Any alteration of Earth's atmosphere by chemical, particulate or biological material is_____

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about any alteration of Earth's atmosphere caused by chemical, particulate, or biological materials.

2. **Identifying Key Terms**: The key terms in the question are "alteration," "Earth's atmosphere," "chemical," "particulate," and "biological material."

3. **Defining the Concept**: An alteration in the atmosphere refers to any change that negatively affects the quality of the air we breathe.

...