How Can We Reduce The Amount Of Traffic...
Motoring0 min ago
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I was told by someone who'd been told by their doctor that normal, 'clean' nose mucus would be colourless, but the various colours you can get (yellow, green, blue) are caused by bacteria (or virii?) living in it. Note this refers to 'nose product' rather than something hawked up after a good cough.
Apparently black is just dirt!