Which is not correct about harmful effect of SPM of 2.5 `mu`m or less

Options

A. It can directly enter our circulatory system
B. It can causes inflammation and damage to the lungs
C. It can be inhaled into lungs
D. It can cause respiratory problems.

Answer

### Step-by-Step Text Solution:

1. **Understanding SPM**: Suspended Particulate Matter (SPM) refers to tiny particles in the air that can be inhaled. Particles that are 2.5 micrometers or less in diameter are particularly concerning for human health.

2. **Effects of SPM**:
- These fine particles can be inhaled deeply into the lungs.
- They can cause various respiratory issues, including inflammation, irritation, and damage to lung tissues.
- Long-term exposure to SPM can lead to serious health problems, including premature death.

3. **Analyzing the Options**:
- The question asks which statement about the harmful effects of SPM is **not correct**.
- The options include:
- It can directly enter our circulatory system.
- It can cause inflammation and damage to lungs.
- It can be inhaled into lungs and can cause respiratory problems.

4. **Identifying the Incorrect Statement**:
- The statement "It can directly enter our circulatory system" is incorrect.
- While SPM can cause significant respiratory issues, it does not directly enter the circulatory system. Instead, it affects the lungs primarily.

5. **Conclusion**: Therefore, the correct answer to the question is that the statement "It can directly enter our circulatory system" is not correct regarding the harmful effects of SPM of 2.5 micrometers or less.