According to central pollution Contril Board [CPCB] what size (in diameter) of particulate is responsiblefor causing greater harm to human health?

Options

A. `3.5 micrometers`
B. `2.5 micrometers`
C. `4.0 micrometers`
D. `3.0 micrometers`

Answer

To solve the question regarding the size of particulate matter responsible for causing greater harm to human health according to the Central Pollution Control Board (CPCB), we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks for the specific size of particulate matter that is most harmful to human health, as defined by the CPCB. The options provided are 3.5 µm, 2.5 µm, 4.0 µm, and 3.0 µm.

2. **Research on Particulate Matter**: Particulate matter (PM) is categorized based on its size. The smaller the particulate matter, the deeper it can penetrate into the respiratory system.

3. **Identifying the Harmful Size**: According to the CPCB and various health studies, particulate matter that is 2.5 micrometers (µm) or smaller (often referred to as PM2.5) is known to pose significant health risks. These particles can be inhaled deeply into the lungs and can cause various respiratory issues.

4. **Conclusion**: Based on the information provided, the size of particulate matter that is responsible for causing the greatest harm to human health is 2.5 µm. Therefore, the correct answer is option 2: 2.5 µm.

### Final Answer:
The size of particulate matter responsible for causing greater harm to human health, according to the Central Pollution Control Board (CPCB), is **2.5 µm**.

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