Which one of the following in not an air pollutant ?

Options

A. Pollen from plants
B. Phosphates
C. Carbon monixide
D. Hydrocarbon

Answer

To determine which of the following is not an air pollutant, we will analyze each option provided in the question.

### Step-by-Step Solution:

1. **Identify the Options**: The options given are pollen from plants, phosphates, carbon monoxide, and hydrocarbons.

2. **Analyze Pollen from Plants**:
- Pollen grains are produced by plants during their reproductive season.
- They are lightweight and can become airborne, leading to allergic reactions in humans.
- Since pollen can be present in the atmosphere and can cause allergic responses, it is considered an air pollutant.

3. **Analyze Phosphates**:
- Phosphates are primarily associated with agricultural runoff and are a major source of pollution in aquatic environments such as lakes and streams.
- They do not significantly contribute to air pollution; instead, they lead to water pollution.
- Therefore, phosphates are not classified as air pollutants.

4. **Analyze Carbon Monoxide**:
- Carbon monoxide (CO) is a colorless, odorless gas that is produced from incomplete combustion of fossil fuels.
- It can bind to hemoglobin in the blood, forming carboxyhemoglobin, which impairs oxygen transport and can lead to serious health issues.
- As such, carbon monoxide is indeed an air pollutant.

5. **Analyze Hydrocarbons**:
- Hydrocarbons are organic compounds made up of hydrogen and carbon.
- They can be released into the atmosphere from vehicle emissions and industrial processes.
- Hydrocarbons contribute to air pollution and are known to be greenhouse gases that can lead to global warming.

6. **Conclusion**:
- Among the options analyzed, pollen, carbon monoxide, and hydrocarbons are all considered air pollutants.
- Phosphates, on the other hand, are primarily associated with water pollution and do not contribute to air pollution.
- Therefore, the correct answer is **phosphates**.

### Final Answer:
**Phosphates** are not an air pollutant.

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