Particulate matter pollution, consisting of microscopic particles suspended in the air, is a significant environmental and public health concern. These particles vary in size and composition, ranging from coarse dust to fine particles small enough to penetrate deep into the lungs and even enter the bloodstream.

PM pollution arises from diverse sources such as vehicle emissions, industrial activities, agricultural practices, and natural events like wildfires. Once released into the atmosphere, these particles can travel long distances, affecting air quality regionally and globally.