Six weeks ago, an 18-year-old male patient showed up to NYU Winthrop Hospital in Long Island complaining about chest pain, nausea, fever, and shortness of breath. Initially, doctors thought he had pneumonia, due to his X-rays showing “haziness” in the lungs. Within 48 hours, says Melodi Pirzada, chief of pediatric pulmonology at the hospital, the patient’s condition worsened and he was sent to the ICU. There he was diagnosed with ARDS, a condition associated with acute lung injury. He was connected to a breathing tube and placed in a medically induced coma for one week.

The doctors were baffled as to how a healthy 18-year-old could become so sick, until the patient’s mother showed up at the hospital with something she’d dug up from her son’s wastebasket. It was a vaporizer cartridge with the label TKO Extracts, a licensed company based in California that sells THC products; the cartridge was later confirmed to be a counterfeit version of the company’s product, Pirzada says. Upon questioning, the man’s girlfriend told doctors that he had used the cartridge three days before he was admitted to the hospital. After being treated with steroids, the patient ultimately recovered, and was released from the hospital after two weeks.

Just one day later, a second patient showed up with completely different symptoms, including various nodules in the lungs; the 19-year-old suffered from coughing and chest pain, and had lost so much weight in the span of just two weeks that doctors initially suspected he had cancer. When a biopsy ruled that out, the patient said that he too had been using THC cartridges for the past three months, all of which had been purchased on the black market. (Marijuana is not legal for recreational purchase in New York state.)

Pirzada was baffled. Though she had only personally treated two such cases, in her 25 years of practice, she had never seen young, seemingly healthy men get so sick within such a short period of time. “It’s becoming very scary. Every day, new cases are adding up,” says Pirzada. “Because we didn’t have this problem three months ago.”

Indeed, what happened to the two men in Long Island has been happening across the country. As the dangers of e-cigarettes in general become more apparent, with the CDC announcing last week that it was aware of 193 potential cases of severe lung illness in 22 states linked to vaping (and one death in Illinois officially linked to vaping), the potential long-term health risks of vaping are becoming increasingly clear, from breathing difficulties to eye and airway irritation. And while it’s unclear exactly how many of these cases are attributable to products containing THC, as opposed to traditional nicotine e-cigarettes, Dr. Ileana Arias, senior scientific advisor and acting deputy director for non-infectious diseases at CDC, noted on a Friday conference call that “in many cases” patients had reported using THC-containing products, though the CDC declined to specify exactly how many.

In California alone, where recreational marijuana is legal, there have been 28 potential cases of acute lung disease among people who had recently vaped cannabis products, according to a spokesperson from the California Department of Public Health (CDPH). On August 12th, the CDPH released a health alert regarding a “cluster” of at least seven healthy adults in Kings County, California, all of whom had been admitted to hospitals between July and August 2019, and all of whom had presented with symptoms of severe acute pulmonary disease, including coughing and shortness of breath, and in some cases fever and vomiting. All seven of these cases — including an additional one reported following media coverage of the initial press release — were linked to THC vapes that had been purchased off the black market, Nancy Gerking, assistant director of public health of Kings County tells Rolling Stone, adding they were purchased at temporary, unlicensed “pop-up shops” in the area.