Particulates are dust and other particles floating around in the air. PM
10 particulates have a diameter of 10 micrometers or less. The difference between PM
10 and PM
2.5 is simply a matter of size - while PM
2.5 is fine, PM
10 is larger and coarser.
Where does it come from?
Microscopic dust, soot, and smoke from construction, mining, transport, and agriculture can blow in from far away, or come from localized sources. Chemical reactions in the atmosphere from industry and vehicle emissions (including tiny fragments of rubber from tires and metal from brakes) are also sources of particulate matter.
There are naturally occurring coarse particles which include salts, pollen, and fragments of bacteria.
What are its effects?
10 is less than a tenth of the width of human hair and is easily inhaled. It irritates your nose and throat and can trigger a whole range of allergic reactions.
Coarse particles can be expelled through coughing and sneezing but, if they get into your lungs, they can bring on asthma attacks and an increased risk of bronchitis, lung cancer, and even premature death. They can also cause stroke, heart attack, and high blood pressure.