An e-cigarette user has been diagnosed with a rare form of lung scarring which is usually seen in metal workers, a study has revealed.
The case study, published in the European Respiratory Journal, suggests the condition in the lungs of an unnamed 49-year-old woman was likely caused by vaping.
Hard-metal pneumoconiosis can result in permanent scarring, breathing difficulties and chronic coughing.
The woman vaped cannabis oil – which has been linked to many of the hundreds of cases of lung illness in the US have been linked to.
When researchers in San Francisco tested the patient’s e-cigarette they found cobalt and other toxic metals – nickel, aluminium, manganese, lead and chromium – in the vapour produced by the device, which they concluded came from the heating coils found inside it.
They believe it is the first example of metal-induced toxicity in the lung following vaping.
One of the authors of the case study, Kirk Jones, clinical professor of pathology at the University of California, said: “Hard-metal pneumoconiosis is diagnosed by looking at a sample of patient’s lung tissue under the microscope.
“It has a distinctive and unusual appearance that is not observed in other diseases.
“When we diagnose it, we are looking for occupational exposure to metal dust or vapour, usually cobalt, as a cause.
“This patient did not have any known exposure to hard metal, so we identified the use of an e-cigarette as a possible cause.”
Co-author Rupal Shah said: “Exposure to cobalt dust is extremely rare outside of a few specific industries.
“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.
“We think that only a rare subset of people exposed to cobalt will have this reaction, but the problem is that the inflammation caused by hard metal would not be apparent to people using e-cigarettes until the scarring has become irreversible, as it did with this patient.”
Professor Jones added: “People who vape are often looking for a safer alternative to smoking. But as lung physicians, it is our job to be concerned about the substances that are inhaled into the lung, particularly those substances that can bypass our usual defence mechanisms such as these ultra-fine mists.
“We believe it is likely not just that this will happen again, but that it has happened already but not been recognised. One of our major reasons for publishing this case history is to inform our colleagues about the possible risks involved with vaping.”
The case study comes as the European Respiratory Society said it cannot back vaping as a safe aid to quitting smoking.
It said it cannot recommend tobacco harm reduction strategies and that there is no evidence alternative nicotine products are safe.
In an editorial, the ERS Tobacco Control Committee said current health policies are based on “well-meaning but incorrect or undocumented claims or assumptions”.
“Evidence on the safety and the effectiveness of alternative nicotine delivery products as a smoking cessation tool is still lacking, while use of nicotine-containing products is spreading to non-smokers, which is most alarming,” the European body said.
Co-author of the editorial Jorgen Vestbo, professor of respiratory medicine at the University of Manchester, said: “E-cigarettes are harmful, they cause nicotine addiction and can never substitute for evidence-based smoking cessation tools.
“The medical profession as well as the public should be concerned about a new wave of lung diseases caused by a product which is heavily promoted by the tobacco industry.”