Cobalt lung (Photo: University of California San Francisco)

As the total number of e-cigarette and vaping-related injuries (EVALI) reaches 2,291 across all 50 states, researchers in California are unveiling a new potential danger of vaping: cobalt lung.

The news comes from a case study published in the European Respiratory Journal this week which focuses on a 49-year-old in California who developed the rare disease after vaping for just six months. The patient, a dog trainer by trade, sought out medical help when he began experiencing symptoms like shortness of breath and coughing — which aligned with the pneumonia-like cases of EVALI.

Although doctors initially thought considered it a vaping illness, the patient’s lungs showed something else, the distinct scarring of lung tissue that is typically only seen in those who work with hard metals. The condition — technically known “hard-metal pneumoconiosis” — is a “rare but serious disease of the lungs associated with inhalational exposure to tungsten or cobalt dust,” according to the NIH.

After observing the lung tissue, the researchers from the University of California, San Francisco performed tests on the vaping product, which contained the hard metal cobalt, among others. In a statement released to reporters, the researchers expressed shock at the development.

"Exposure to cobalt dust is extremely rare outside of a few specific industries,” Rupal Shah MD, assistant professor of medicine in the division of pulmonary, critical care, allergy, and sleep medicine at the University of California, San Francisco, said. “This is the first known case of a metal-induced toxicity in the lung that has followed from vaping and it has resulted in long-term, probably permanent, scarring of the patient's lungs.”

In an interview with Yahoo Lifestyle, Kirk Jones MD, clinical professor of pathology at the University of California, San Francisco said he’s only seen three previous cases of cobalt lung in his entire career, including one involving a sawmill worker and another in a dental worker. “It’s always been kind of a work-related disease so it was peculiar in this patient because they didn’t have any exposures that we knew of,” Jones tells Yahoo Lifestyle. “Until we tested the vaping device.”

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The vaping device the patient was using, called the ZenPen, was found to have e-cigarette liquid containing nickel, aluminum, manganese, and lead — and a metal coil used to heat the liquid. As a result of inhaling this, Jones says the white airspaces of the lung that allow oxygen to flow had been filled up with inflammatory cells.

“There was less room in [the] lungs to breathe,” says Jones. The patient was reportedly treated with steroids and has regained half of the function that was lost in [the] lungs, but will likely have permanent scarring.

Jones says EVALI and cobalt lung develop differently. “With the EVALI cases, patients suffer an acute collapse and damage of the lung that comes on pretty quickly, probably over a few hours,” he explains. “Whereas our case is more of an immune reaction. It's kind of an allergic reaction...to the metal found in people who are susceptible to cobalt and the disease would develop over the course of weeks or months.”

The researchers are spreading the word about the case of cobalt lung in part because they fear it’s not the only one. “I think that cobalt is probably in a lot of these e-cigarettes,” says Jones. “Maybe a small percentage of patients that use them will end up with the disease — and probably already have, but it hasn't been recognized yet.”

Related Video: ‘It Is Not Harmless’: Dentists Voice Concern Over Vaping

Editor's Note: This story has been updated to clarify the patient’s pronouns.

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