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What are the causes of black phlem?
1 doctor weighed in

Dr. Dennis Clifford
Internal Medicine - Pulmonary Critical Care
In brief: Several
Old blood, carbon from dust, carbon from smoke are all possible causes.

In brief: Several
Old blood, carbon from dust, carbon from smoke are all possible causes.
Dr. Dennis Clifford
Dr. Dennis Clifford
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Dr. Aaron Milstone
Board Certified, Internal Medicine - Pulmonology
23 years in practice
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