Doctors removed rubbery black gunk from a man's lungs, but it wasn't because he had vaped or smoked cigarettes. Instead, the culprit was Mother Nature.  

The New England Journal of Medicine documented the unusual case of a man who went to the emergency room after being exposed to wildfire smoke for hours. 

The 87-year-old was having problems breathing, and his blood oxygen saturation was dangerously low, even though doctors found no signs of thermal injuries or heat-related burns. 

The man went on mechanical ventilation. When doctors examined him further, they realized his condition was deteriorating because black structures were blocking his airways.

Black Gunk Found in Man's Lungs Exposes an Even Darker Side of Wildfire Smoke https://t.co/q18nUhbzvG

— Gizmodo (@Gizmodo) April 21, 2026

"A diagnosis of bronchial casts from the inhalation of particulate matter from forest-fire smoke was made," the NEJM wrote. "The casts were removed with a cryoprobe."

According to Medical News Today, bronchial casts "consist of cellular material and mucus" and form "rubbery plugs" in airways. The issue can be life-threatening if not treated. 

Fortunately, the man's condition improved after the procedure, and he left the hospital after a seven-day stay. Two weeks later, doctors confirmed his breathing had returned to normal. 

Still, the news will likely put people on notice as wildfire season approaches. As Gizmodo noted, the man's hospital stay "starkly illustrates the damage forest fires can do to our lungs." 

Additionally, the Centers for Disease Control and Prevention noted that wildfire smoke inhalation is particularly dangerous for people with "asthma, Chronic Obstructive Pulmonary Disease, diabetes, chronic kidney disease, or heart disease."

The NEJM also spotlighted the case as part of a series demonstrating how a changing climate impacts human health. 

To be sure, air pollution is a direct threat to our respiratory systems. However, it also drives hotter and drier conditions that fuel wildfires. In February, fire weather experts warned that a snow drought could lead to an early and severe wildfire season in the western United States. 

As images of the bronchial casts surfaced, people reacted with a mixture of shock at the severity of the issue and gratitude for the medical professionals who saved the man. 

"'Holy Smokes' that picture surprised me," one Instagram user wrote. "WOW." 

"This is an amazing treatment," a New York Post reader remarked. "It's great that this man survived." 

Another agreed: "Both the malady and the treatment are pretty extraordinary."

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