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 observed in newborns where their skin takes on a bluish tint due to a lack of oxygen in the blood. This condition can be indicative of underlying heart problems.

2. **Identifying the Cause**:
- The primary cause of blue baby syndrome is the presence of nitrates in drinking water. Nitrates can interfere with the blood's ability to carry oxygen, leading to the symptoms associated with the syndrome.

3. **Mechanism of Nitrate Effect**:
- When nitrates are ingested, they can be converted into nitrites in the body. Nitrites can bind to hemoglobin, forming methemoglobin, which is unable to effectively carry oxygen. This results in a decreased oxygen supply to the tissues, causing the characteristic blue coloration.

4. **Sources of Nitrate Contamination**:
- Nitrate contamination in drinking water often comes from agricultural runoff, where fertilizers containing nitrates leach into groundwater. This is a significant environmental concern, especially in rural areas where agricultural practices are prevalent.

5. **Exclusion of Other Options**:
- Other contaminants such as carbonates, phosphates, and sulfates are not associated with blue baby syndrome. They may cause other health issues, but they do not lead to the oxygen deprivation characteristic of this syndrome.

6. **Conclusion**:
- Based on the information gathered, we can conclude 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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