Painful skeletal deformity called itai-itai is caused due to

Options

A. Cd
B. Hg
C. CO
D. `NO_(2)`

Answer

### Step-by-Step Solution

1. **Identify the Disease**: The question asks about a painful skeletal deformity known as Itai-Itai disease.

2. **Determine the Cause**: Itai-Itai disease is specifically linked to exposure to certain environmental toxins.

3. **Analyze the Options**: The options provided are:
- CD (Cadmium)
- Hg (Mercury)
- CO (Carbon Monoxide)
- NO2 (Nitrogen Dioxide)

4. **Select the Correct Option**:
- Itai-Itai disease is caused by cadmium exposure. Therefore, the correct answer is **CD (Cadmium)**.

5. **Explain the Mechanism**: Cadmium pollution leads to cadmium poisoning, which results in various health issues, including:
- Anemia (deficiency of blood)
- Hypertension (high blood pressure)
- Damage to liver and kidneys
- Painful skeletal deformities (Itai-Itai disease)

6. **Characteristics of Itai-Itai Disease**: Itai-Itai disease is characterized by:
- Osteomalacia (softening of bones)
- Severe bone pain
- Renal tubular dysfunction (kidney failure)

7. **Discuss Incorrect Options**:
- **Hg (Mercury)**: Causes Minamata disease, a neurological disorder.
- **CO (Carbon Monoxide)**: Leads to oxygen deficiency in tissues due to the formation of carboxyhemoglobin, but does not cause Itai-Itai disease.
- **NO2 (Nitrogen Dioxide)**: Damages the respiratory tract and increases infection risks, not related to Itai-Itai disease.

### Final Answer
The painful skeletal deformity called Itai-Itai is caused due to **CD (Cadmium)**.

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