A woman wears a cpap machine.Share on Pinterest
No Limit Pictures/Getty Images
  • Tap water, which the CDC categorizes as “unsterile water,” contains a number of pathogens that can cause waterborne illness when inhaled.
  • There are many pathogens that exist in tap water, including Pseudomonas aeruginosa, Legionella spp., Acanthamoeba spp., and Naegleria fowleri.
  • Many Americans are unaware that using tap water in their home medical devices can lead to infections, the CDC found

You should really avoid using tap water in your home medical devices, like humidifiers and continuous positive airway pressure (CPAP) machines, according to new researc from the Centers for Disease Control and Prevention (CDC).

Tap water, which the CDC categorizes as “unsterile water,” contains a number of pathogens that can cause waterborne illness when inhaled.

Many Americans are unaware that using tap water in their home medical devices can lead to infections, the CDC found.

The organization hopes its findings encourage healthcare providers to educate patients about the importance of using sterilized water in their home medical devices.

“When we use CPAP machines or humidifiers in the room that have access to our very sensitive body organ systems, such as the nasal passage, trachea and the lungs, we can be exposed to aerosolized contaminants,” Dr. Saurabh Chatterjee, a professor of environmental and occupational health and medicine with University of California, Irvine’s Program in Public Health, told Healthline.

The CDC conducted a survey in August 2021 to gauge people’s perceptions about appropriate water use in home medical devices.

They found that a third of participants — particularly those who were male, lived in an urban environment, or identified as Black — did not know that tap water contains bacteria and other pathogens

Nearly half assumed that tap water could be safely used for rinsing out sinuses, cleaning contact lenses, and in respiratory devices.

About a quarter of participants said they used tap water in their humidifiers and CPAP machines.

The CDC hopes the results encourage people to sterilize tap water before using it in their home medical devices.

There are many pathogens that exist in tap water, including Pseudomonas aeruginosa, Legionella spp., Acanthamoeba spp., and Naegleria fowleri.

In fact, biofilm-associated pathogens like Pseudomonas and Legionella spp. make up a significant percentage of the 120,000 hospitalizations and 7,000 deaths due to waterborne diseases annually, according to the CDC’s report.

Though pathogens in unsterile water can lead to infections through various routes, including drinking, most water-related infections are due to inhalation.

Our mouths and gastrointestinal tracts are not sterile and the minerals in tap water are actually healthy for our bodies, says Dr. Michelle Cao, a pulmonary and critical care medicine physician with Stanford Health Care.

“The intestinal tract has very strong immune defenses but that cannot be said for our lungs,” says Chatterjee.

With a CPAP machine, for example, the pathogens can be inhaled, which can lead to an infection, says Dr. Amesh Adalja, a senior scholar at the Johns Hopkins University Center for Health Security and an infectious disease expert.

“The device involves aerosolization of the water which allows it to penetrate into the respiratory system — that is not equivalent to drinking tap water,” Adalja said.

The symptoms can be similar to those associated with pneumonia, says Adalja. Think: cough, chest pain, and shortness or breath.

Once inhaled, some of the pathogens can stay in the lungs and cause an active when an outside factor triggers an infection, according to Cao.

The odds of getting sick depend on the person’s health, the CDC says, and those most at-risk for contracting a serious infection include the older adults, infants, young kids, and people with weakened immune systems or those with chronic conditions like chronic lung disease.

When it comes to home medical devices, you want to use clean, sterilized water.

If you don’t have easy access to distilled water, the CDC’s report notes that tap water can be sterilized by boiling it for five minutes and then letting it cool before using it for medical purposes

When determining the type of water you use in your medical devices, it’s important to evaluate your personal risk factors and environment, says Cao.

For example, some countries bottled water may not be sterile enough to use in a CPAP machine and people with serious disease may not be able to pause using their devices if sterile water is not available.

“A patient who requires the use of a home mechanical ventilator for life support would not be able to stop treatment temporarily even if no distilled water is available, versus a patient with obstructive sleep apnea who may tolerate no CPAP use for a few nights if distilled water is not available,” Cao said.

The CDC also recommends regularly cleaning and disinfecting home medical devices, as pathogens can grow and multiply in these devices

“Another important issue is proper cleaning of plastic pipes and inner surfaces of humidifiers to ensure that no bacterial growth or bacterial toxins are adhering to the surfaces,” says Chatterjee.

A new report from the CDC found that many Americans didn’t know that tap water shouldn’t be used in their home medical devices. Tap water contains pathogens, and though it’s safe to drink, it can lead to infections when inhaled, especially among young children, the elderly, and people with weakened immune systems. People should use distilled water, or tap water that’s been boiled for five minutes, in their home medical devices to avoid getting sick.