7. Pollution that is will break down over time. A good example would be

Biodegradable / Grass clippings.
Persistent / An aluminum can.

Pollutants that is biodegradable will break down with time, for example, grass clippings.  

•The wastes emerging from the households, which can be decomposed by microbes are known as the biodegradable pollutants.  

•These components can be easily degraded with time by naturally occurring agents like water, oxygen, UV rays, acid rains, and microbes.  

•Some of the examples of biodegradable pollutants are wastes products from animal and humans waste, dried leaves, plant products, grass, flowers, and fruits.  

Thus, biodegradable pollutants get dissociate with time, and one of the example is grass clippings.

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