Thousands of people accidentally mix ammonia and bleach every year. Can it kill you?

Ammonia and bleach are two very common chemicals used by millions of Americans every day. You might assume that mixing them can create an even more powerful DIY household cleaner to fight grime and germs. But this type of home chemistry experiment can have deadly consequences.

Bleach, which contains sodium hypochlorite (NaOCl), is often used to clean and disinfect surfaces, Kaitlyn Brown, PharmD, clinical managing director of America’s Poison Centers, tells TODAY.com. Ammonia (NH3) is found in many household cleaning products, says Brown — including glass cleaners, tile cleaners, multipurpose or bathroom cleaners and certain drain cleaners.

If handled and used properly on their own, ammonia and bleach are safe and effective household cleaners, but together, they pose serious health risks.

Can mixing bleach and ammonia kill you?

Yes, you can die from inhaling the gas that is produced when you mix ammonia and bleach, which is called chloramine gas, Brown says. It's very rare, but possible, she adds.

The extent of injury from exposure to chloramine gas will depend on the concentration of the bleach and ammonia and length of exposure, she adds.

In higher concentrations — which can occur from mixing large quantities or if the gas is released into a small space without ventilation, says Brown — chloramine gas can cause serious harm.

"Even if you've only been breathing it in for a little while, that can cause burns along the airway and respiratory tract," says Brown, adding that prolonged exposure can result in injury to the lungs.

"It can cause a lot of inflammation and swelling in the lungs that can make it difficult to breathe and require hospitalization, oxygen or support with ventilation," Brown explains.

Depending on the severity of the damage, this may affect a person's longterm lung function, Brown adds.

What are the symptoms of mixing bleach and ammonia?

When chloramine gas is inhaled, it enters the respiratory tract and reacts with the moisture of the membranes lining your nostrils, mouth and throat, which, “as you can imagine, (is) very irritating,” Brown says.

When exposed to lower concentrations of chloramine gas, people may experience milder symptoms. “They might notice their eyes are watering, their nasal cavity feels sore or their throat feels scratchy and they might have a mild cough,” says Brown.

People may experience shortness of breath or wheezing, she adds.

According to the Washington State Department of Health, these are the most common symptoms of mixing ammonia and bleach:

  • Coughing

  • Nausea

  • Shortness of breath

  • Watery eyes

  • Chest pain

  • Irritation to the throat, nose and eyes

  • Wheezing

  • Pneumonia and fluid in the lungs

How do you know if you mixed ammonia and bleach?

“You usually have pretty early warning signs that something’s going on,” says Brown. Chloramine gas has a very strong and unpleasant odor, which, in addition to its irritating effects, quickly indicates that you are cleaning with a chemistry experiment.

However, sometimes it can be less obvious because many cleaning products have strong odors, Brown adds. “It can be challenging if you’re really deep cleaning for a long time and you get fumes from other products. You may not realize that you’ve produced an actual dangerous gas."

In 2021, there were 3,480 human exposures to chloramine gas, according to the most recent U.S. National Poison Data System (NPDS) annual report. The vast majority of these exposures occurred among adults and were unintentional. About 500 people were treated in a health care facility, but many of the exposures had minor medical outcomes, according to the report.

“In most cases, people are accidentally mixing these household products and producing smaller concentrations of the gas and not experiencing those extreme effects,” says Brown.

It doesn’t take that much of either chemical to produce chloramine gas, either. “Any sort of mixture can liberate the gas,” says Brown.

This includes pouring bleach and ammonia (or products that contain these) into a bucket or toilet bowl together, for example. But the gas can also be formed if you spray a surface with a bleach-containing cleaner and don’t let it dry then spray an ammonia-containing cleaner, says Brown.

What should you do if you mix bleach and ammonia?

If you realize you mixed bleach and ammonia or you suspect you have been exposed, get as far away from the source as possible. "You're going to want to leave the environment for fresh air," says Brown, whether that's another room or outside.

The typical symptoms, like irritation, coughing and watery eyes, should start to improve almost immediately once a person moves into fresh air. "In most cases, symptoms will resolve over a period of an hour or two, especially in those patients who don’t have any sort of preexisting asthma or ... lung problems," says Brown.

Contact poison control at 1-800-222-1222 or visit PoisonHelp.org if you have questions or concerns, Brown says. "We usually can help you through a situation in two to three minutes," she adds.

If you're having trouble breathing, call 911, says Brown. If your symptoms do not improve after moving to fresh air or they worsen, go to a hospital or urgent care for further treatment.

“You’re also going to want to air out that environment and make sure that when you return to that environment, you don’t smell any of those fumes,” says Brown. So, open any doors or windows and turn on fans to help ventilate the space, and dispose of the mixture of cleaning products down the drain.

How to avoid mixing bleach and ammonia

Always read the ingredient list on cleaning products, says Brown, which will indicate whether a product has bleach or ammonia.

Additionally, only use products as directed, she says, which means no mixing or using products for purposes that are not indicated on the label.

When bleach is mixed with vinegar, for example, this can also create a toxic gas that can irritate the respiratory tract, TODAY previously reported.

Cleaning products should be kept in their original containers with the ingredients listed, says Brown, but if you decide to transfer products into new container or reusable spray bottle, make sure to label everything.

"For any cleaning product, it's always good to keep it stored when it's not in use, so up and away or in a locked cabinet that children can't access," says Brown.

Finally, Brown encourages people to reach out to poison control — either by phone or online — anytime they have questions or concerns instead of searching on the internet. "I think it's quicker, and you'll get better information from experts," says Brown.

This article was originally published on TODAY.com