Laxative effect is caused by

Options

A. Nitrates
B. Sulphates
C. Lead
D. Fluoride

Answer

**Step-by-Step Solution:**

1. **Understanding Laxative Effect**: The laxative effect refers to the ability of certain substances to stimulate bowel movements or loosen stools, which can lead to diarrhea if consumed in excess.

2. **Identifying the Context**: The question relates to the quality of drinking water and the substances that can affect human health when present in high concentrations.

3. **Reviewing the Options**: The question likely provides multiple-choice options. Based on the context, we need to identify which substance is known to cause a laxative effect when present in high concentrations in drinking water.

4. **Analyzing Sulphates**: Sulphates are known to have a tolerable limit in drinking water, which is set at less than 500 ppm (parts per million). When the concentration of sulphates exceeds this limit, it can lead to gastrointestinal disturbances, including the laxative effect.

5. **Comparing Other Options**:
- Nitrates can lead to serious health issues, such as stomach cancer, when present in excess.
- Lead is harmful and can damage kidneys when found in high concentrations.
- Fluorides can cause dental issues like brown mottling of teeth and can be harmful to bones.

6. **Conclusion**: Since sulphates are specifically mentioned to cause a laxative effect when present in high concentrations, we conclude that the answer to the question is sulphate.

**Final Answer**: Sulphate

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