The phrase
"aerosol precursors" refers to substances or chemicals that can transform or react in the air to form aerosols. These aerosols are tiny particles suspended in the atmosphere, which can have various effects on the environment, climate, air quality, and human health.
Aerosol precursors can come from natural sources, such as volcanoes or forest fires, as well as from human activities, like burning fossil fuels or using certain industrial processes.
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