Blue-baby syndrome is caused by drinking water contaminated with

Options

A. Carbonates
B. Phosphates
C. Sulphates
D. Nitrates

Answer

**Step-by-Step Solution:**

1. **Understanding Blue-Baby Syndrome**: Blue-baby syndrome is a condition that affects infants, leading to a bluish discoloration of the skin due to a lack of oxygen in the blood.

2. **Identifying the Cause**: The primary cause of blue-baby syndrome is the ingestion of water that is contaminated with certain compounds.

3. **Recognizing Contaminants**: Among the common contaminants, nitrates are known to be the main culprit. Nitrates can be found in water sources that are contaminated due to agricultural practices, particularly in farming communities that use fertilizers and manures.

4. **Mechanism of Action**: When infants consume formula milk made with nitrate-rich water, their bodies convert nitrates into nitrites. Nitrites then bind to hemoglobin in the blood, converting it into methemoglobin, which cannot effectively carry oxygen.

5. **Risk Factors**: Infants younger than 3 months are particularly at risk for developing blue-baby syndrome due to their immature digestive and metabolic systems.

6. **Conclusion**: The correct answer to the question is that blue-baby syndrome is caused by drinking water contaminated with nitrates.

**Final Answer**: Blue-baby syndrome is caused by drinking water contaminated with nitrates.

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