What would be the consequence of presence of following in water ?
(i) Sulphates `gt` 500 ppm
(ii)Fluorides between 2 ppm -10 ppm `gt` 10 ppm
(iii) Nitrates `gt `50 ppm

Explanation

To address the consequences of the presence of the specified substances in water, we can analyze each one step by step:

### Step 1: Sulphates > 500 ppm
- **Consequence**: When the concentration of sulphates in water exceeds 500 ppm, it can lead to a laxative effect. This means that consuming water with high sulphate levels can cause gastrointestinal disturbances, such as diarrhea. At moderate levels, sulphates are generally harmless, but at elevated concentrations, they can pose health risks.

### Step 2: Fluorides between 2 ppm - 10 ppm and > 10 ppm
- **Consequence (2 ppm - 10 ppm)**: When fluoride levels are between 2 ppm and 10 ppm, it can lead to dental issues, specifically brown mottling of teeth, also known as dental fluorosis. This condition affects the appearance of teeth and can cause aesthetic concerns.

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