Lung disease are four times more in Urban areas than Rural area. This is due to the presence of which

Options

A. `SO_(2)`
B. `CO_(2)`
C. `N_(2)`
D. Water-vapour

Answer

**Step-by-Step Solution:**

1. **Understanding the Problem:**
The question states that lung diseases are four times more prevalent in urban areas compared to rural areas. We need to identify which gas is primarily responsible for this increase in lung diseases.

2. **Identifying Possible Gases:**
The options provided are:
- SO2 (sulfur dioxide)
- CO2 (carbon dioxide)
- N2 (nitrogen)
- Water vapor

3. **Analyzing SO2 (Sulfur Dioxide):**
- Sulfur dioxide (SO2) is known to cause respiratory issues when present in high concentrations.
- Common lung diseases associated with SO2 exposure include asthma, chronic bronchitis, and emphysema.
- The acceptable concentration of SO2 is between 5 to 20 parts per billion (ppb), but levels above 35 ppb are harmful.
- Urban areas often have SO2 levels ranging from 100 ppb to as high as 300-500 ppb due to factors like automobile emissions and industrial activities.

4. **Analyzing CO2 (Carbon Dioxide):**
- CO2 is primarily associated with climate change and does not directly cause lung diseases.
- Its increase leads to temperature imbalance rather than respiratory issues.

5. **Analyzing N2 (Nitrogen):**
- Nitrogen (N2) makes up about 70% of the atmosphere and is inert, meaning it does not cause any diseases.

6. **Analyzing Water Vapor:**
- Water vapor is a natural component of the atmosphere and does not cause lung diseases.

7. **Conclusion:**
- Based on the analysis, the gas responsible for the higher prevalence of lung diseases in urban areas is **sulfur dioxide (SO2)**.

**Final Answer:**
The presence of **sulfur dioxide (SO2)** is the primary reason for the higher incidence of lung diseases in urban areas compared to rural areas.

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