A voluntary recall of millions of CPAP breathing machines, used mainly to treat sleep apnea, has many users wondering if they’ve been inhaling cancer-causing toxins in their sleep.

At least 25 million U.S. adults have sleep apnea, a potentially serious sleep disorder in which breathing repeatedly stops and starts throughout the night, preventing them from getting a good night’s sleep. A continuous positive airway pressure, or CPAP machine, pushes a steady stream of air into a user’s nose and mouth, keeping airways open.

But CPAP users now face the choice of using a machine that the company says could actually hurt their health – or going without, which means they won’t get a decent night’s sleep.

In June, the manufacturer Philips voluntarily recalled millions of its popular DreamStation CPAP machines because of possible health effects.

Philips said sound-dampening foam used in the DreamStation “may degrade into particles” and “off-gas… chemicals.” The FDA says breathing those in could “result in serious injury which can be life-threatening” or “cause permanent impairment” ranging from irritation to asthma… or even “toxic or carcinogenic effects.”

“It’s caused a lot of anxiety,” said Dr. David Claman, the medical director of the Sleep Disorders Center at University of California, San Francisco. He says many of his patients have recalled machines.  

CBS News consumer investigative correspondent Anna Werner asked, “What are you telling your patients to do?”

“I’m advising the more severe patients to stay on CPAP. and then I’m to some degree in the milder cases, letting them choose, because I also feel uncomfortable with saying I can’t know that this is safe.” 

Werner heard from some frustrated sleep apnea sufferers, including James Colbert, who described his life 13 years ago before he started using a CPAP machine (including, for the past two years, the Philips DreamStation): “There were times where I would literally fall asleep mid-sentence talking to someone because I was so exhausted from not going to sleep the night before.”

Since using CPAP, Colbert said, “I actually woke up refreshed, and could go throughout the course of my day with, you know, a ton of energy that I needed for work or, you know, time with my family.”  

Jozefa Kozyra, of Lehighton, Pennsylvania, relied on her DreamStation to sleep so she could provide round-the-clock care for her son, Kamil, who has muscular dystrophy.

Kamil told Werner, “She needs to bathe me, dress me, feed me, and other exercises to do during the day.”

But since the recall, she said her doctor advised her not to use the machine – and she’s struggling without it. “I’m very tired, I’m very slow,” said Jozefa.

Werner asked, “How much sleep do you get without the machine?”

“When I don’t have machine now, two hours, three hours,” she replied.

Her son said Medicare turned her down for a replacement machine, and she can’t afford to spend hundreds of dollars to buy a new one.

Kamil said, “She called several times to her insurance and Medicare, and they’re saying, because it hasn’t been five years, even though it’s not her fault at all, they’re not willing to pay for a new machine.”

Philips now says it will “replace or repair devices” … “within approximately 12 months” once the FDA approves a solution.

It’s unclear how many patients have suffered health effects; the company said it received complaints on 0.03 percent of its machines in 2020, including some the FDA sent about “the presence of black debris/particles” in some machines.

Philips said its testing revealed “possible risks,” which raises questions for Dr. Claman: “Is this just the tip of the iceberg, or is this all there is?”

As for James Colbert, he said the risks of not wearing the machine are greater than possible unknown health effects, so he’s continuing to use his. 

“I cannot afford to not use it, because I would get so little sleep in,” Colbert said. “And if I slept without it, I would stop breathing so many times during the course of the night.”

But he has a message for Philips: “To tell me that it could take up to a year? That’s a year that I could be putting myself in jeopardy,” Colbert said. “People just cannot afford to wait 12 months for a resolution.”

Colbert has also joined a lawsuit against Philips, he said, to push them to act faster on this problem.

Philips did not respond to CBS News’ request for comment on the lawsuit. (In April, Philips came out with a new machine, the DreamStation 2, which it says is not affected by this recall.)

Connecticut Senator Richard Blumenthal is demanding answers about how many people are affected by the recall, and what Philips is doing to help them.

There’s one other potential problem that may be coming into play here:  many people with the machines use an ozone cleaning system to clean them, and that may be degrading the sound abatement foam faster.