Non-insect material (likely nasal mucus or phlegm)

Nasal passages or upper respiratory tract

Not applicable (non-living material containing glycoproteins and cells)

Accumulates in response to inflammation, allergies, or infection; expelled through sneezing, coughing, or blowing.

Benefits: Traps dust, pollen, and pathogens to protect the lungs. Risks: If persistent or accompanied by symptoms like fever, it may indicate a respiratory infection.