Water is safe for human consumption only when it is free from floating substances, unwanted smells, and micro-organisms. These three factors can have negative effects on our health, making it important to ensure that the water we drink is clean and safe.

Floating Substances:
- Floating substances in water can include debris, particles, and pollutants. These substances can come from various sources such as industrial waste, agricultural runoff, or natural sources like leaves and dirt.
- Drinking water with floating substances can be harmful as these particles may contain harmful chemicals or bacteria that can cause illness or infections.
- It is important to filter or remove these floating substances before consuming the water to ensure its safety.

Unwanted Smells:
- Water with unwanted smells may indicate the presence of pollutants, chemicals, or bacteria. These smells can come from sources like sewage, rotting organic matter, or industrial waste.
- Consuming water with unpleasant smells can not only be unpleasant but also pose health risks. It may indicate the presence of harmful substances that can cause gastrointestinal issues or other health problems.
- To make water safe for consumption, it is necessary to eliminate these unwanted smells through proper filtration or treatment methods.

Micro-organisms:
- Micro-organisms in water can include bacteria, viruses, and parasites. These micro-organisms can enter water through various sources such as sewage, animal waste, or contaminated groundwater.
- Consuming water contaminated with harmful micro-organisms can lead to waterborne diseases such as diarrhea, cholera, or typhoid.
- To ensure the safety of drinking water, it is essential to treat it through processes like disinfection or filtration to remove or kill these micro-organisms.

Conclusion:
In conclusion, water is safe for human consumption only when it is free from floating substances, unwanted smells, and micro-organisms. These factors can have adverse effects on our health, causing illnesses or infections. It is crucial to take necessary measures such as filtration, disinfection, or treatment to ensure that the water we drink is clean and safe.

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