Dangerous Duos: Mixing Cleaning Products Can Be a Deadly Mistake

The yellow-green cloud swirled and spread throughout the Massachusetts restaurant. From it came a strong, pungent odor that caused patrons and staff to flee. The general manager attempted to clear the gas, but in the end he and 13 others had to be hospitalized.

However, the 32-year-old general manager never made it out alive.

Someone, a staff member, had accidentally mixed two cleaners that should never have been combined while cleaning the floor at the restaurant. It’s a mistake that happens far too often. And while some escape alive. Others end up with long-term injuries and others die as a result.

When it comes to cleaning, more isn’t always better. In fact, mixing common household cleaners like bleach and vinegar or ammonia and disinfectants can release toxic fumes that pose serious health risks. While it might seem like combining products could boost their cleaning power, the truth is far more dangerous.

In California, workplace tracking recorded 50+ new asthma cases and nearly 250 injuries or illnesses triggered by improper mixing of disinfectants and cleaning agents (e.g. bleach + ammonia or acids). Building custodians faced injury rates twice that of other workers, with about 6% experiencing chemical-related injuries; 20% of those involved serious burns from exposure to caustic cleaners.

Cleaning your home or workplace should promote health and safety, not compromise it. Yet, many well-intentioned individuals unknowingly mix household cleaners, leading to toxic chemical reactions that can cause serious injury or even death. This is a critical issue for those using both traditional and natural cleaning products.

At Nature Kleen, we believe that cleaning your home or workplace should never come at the expense of your health or the environment. In this blog, we’ll break down the hidden dangers of mixing cleaning products, the science behind harmful reactions, and how you can stay safe using effective, natural alternatives.

Real-Life Tragedies: The Consequences of Mixing Cleaners

The incident at the restaurant, Buffalo Wild Wings in Burlington, MA,  happened in November 2019. The general manager died after inhaling fumes from a mixture of Scale Kleen and Super 8, two cleaning agents containing acid and bleach. A staff member had applied the bleach-based cleaner to a kitchen floor where the acid-based cleaner had been spilled earlier – leading to the emission of chlorine gas.

The staff rushed out of the restaurant a short time later to escape the toxic fumes. But the 32-year-old manager attempted to squeegee the noxious liquid outside before being overcome. He later died of chemical pneumonia. The 13 others who were hospitalized (employees and patrons) were treated and later released.

Red Robin saw a similar case within two weeks of the Burlington tragedy after someone mixed acid and bleach fumes in a Woburn, MA restaurant, which sent three workers to the hospital. Eyewitnesses described seeing green bubbling and severe fume clouds, indicators of chemical reactions.

Even certified green cleaners—like those meeting EPA Safer Choice standards—can become dangerous if mixed. For example, adding vinegar (natural acid) to a bleach-based disinfectant produces chlorine gas. Additionally, hydrogen peroxide, a common “green” disinfectant, reacts violently with bleach. And eco products may contain essential oils or surfactants that, once mixed, create volatile organic compounds (VOCs), worsening indoor air quality and triggering asthma.

There have been other cases of injuries due to mixing cleaners.

Case of Chloramine Gas at Assisted Living Facility

At an Assisted Living Facility in Tennessee, chloramine gas formed when an employee mixed chlorine bleach and ammonia, activating the smoke detector in resident's room where the the employee was attempting to clean up fecal matter. Two employees were evaluated, although fortunately did not suffer lasting injury.

Case of Severe Lung Injury

A 53‑year‑old woman mixing bleach and ammonia in a closed freezer developed chemical pneumonitis, leading to an emergency tracheostomy because her upper airway was compromised. She remained hospitalized for nearly a week.

Case Series from PubMed

A military medical report described three life‑threatening cases in one year of toxic pneumonitis due to inhalation of chloramine gas from bleach + ammonia mixtures; each required prolonged hospitalization and left residual lung damage.

Many believe that combining cleaning products might boost efficacy—but it can be deadly. Mixing even “green” cleaners with conventional ones can spark chemical reactions that release toxic fumes. Below are the key offenders:

Common and Deadly Cleaning Combos to Avoid

1. Bleach + Ammonia = Toxic Chloramine Gas

Ammonia is commonly found in glass and window cleaners, while bleach is prevalent in disinfectants. When mixed, they produce chloramine vapors, which can cause:

• Burning eyes, nose, and throat

• Coughing and shortness of breath

• Nausea and vomiting

• Potentially deadly pulmonary edema (fluid buildup in lungs) 

Even a single exposure to high levels of chloramine gas can be fatal.

2. Bleach + Rubbing Alcohol = Chloroform

Mixing bleach (sodium hypochlorite) with rubbing alcohol (isopropyl alcohol) creates chloroform—a chemical compound that can cause:

• Dizziness and fainting

• Damage to the nervous system, eyes, lungs, skin, liver, and kidneys

• In extreme cases, death 

3. Bleach + Vinegar = Chlorine Gas

Combining bleach with vinegar produces chlorine gas, which can lead to:

• Coughing and breathing problems

• Burning and watery eyes

• Chest tightness and difficulty breathing 

This combination was even used as a chemical weapon during World War I due to its potency.

4. Toilet Bowl Cleaner + Bleach = Chlorine Gas

Mixing an acid-based toilet bowl cleaner with bleach releases chlorine gas, leading to:

• Irritation of the eyes, nose, and throat

• Coughing and breathing problems

• In severe cases, death 

5. Bleach + Drain Cleaners = Chlorine Gas

Bleach + Drain Cleaners

Mixed with acidic drain cleaners with bleach releases chlorine gas, leading to corrosive injury

to skin, lungs, or eyes.

Natural or “green” cleaners are often safer alternatives. However, they can still pose risks when mixed improperly. For example, combining hydrogen peroxide with vinegar creates peracetic acid, a corrosive substance. Always read labels and avoid mixing natural cleaners unless specified by the manufacturer.

6. Hydrogen Peroxide + Vinegar = Peracetic Acid

While both hydrogen peroxide and vinegar are effective cleaners individually, mixing them creates peracetic acid—a corrosive substance that can cause:

• Irritation of the eyes, skin, throat, nose, and lungs

• Potential scarring of the eyes, skin, and respiratory system 

Maintaining safe, effective green cleaning means respecting chemistry—never mixing products, ensuring proper ventilation, and following label instructions. Below are some safety tips to keep in mind.

  Safety Tips: How to Clean Without the Risk

• Never mix cleaning products unless the label explicitly states it’s safe to do so. Mixing cleaning products is a serious safety hazard, not a harmless “hack.”

• Use one product at a time and allow surfaces to dry between applications.

• Ventilate well: open windows, use fans—even “green” products may produce VOCs. Enclosed spaces (bathrooms, kitchens) magnify risks—limited ventilation dramatically raises toxin concentration.

• Use PPE: gloves, goggles, and respirators when needed to minimize exposure.

• Rinse thoroughly between products, if switching formulas.

• Train staff on SDS and hazard communication—restaurants are high-risk. Employers should train and emphasize not to mix cleaning agents. Always provide label guidance, protective gear, and ventilation recommendations.

• Use certified green products (Green Seal, EcoLogo, Safer Choice) and apply them as instructed.

• Store cleaning products safely, out of reach of children and pets. 

• In case of exposure: evacuate, ventilate, seek fresh air, and call 911 or Poison Control (1‑800‑222‑1222) if symptoms appear.

Mixing cleaning products—whether traditional or natural—can lead to dangerous chemical reactions with serious health consequences. Even “green” cleaners containing acids or enzymes can become dangerous when combined with bleach or alkaline chemicals. The safest rule: never mix unless the label explicitly says it’s safe. By understanding the risks and following safety guidelines, you can maintain a clean and safe home environment.

Cleaning doesn't have to be complicated or dangerous. At Nature Kleen, we champion safe, green cleaning by using one trusted non-toxic product at a time. The allure of mixing cleaners for extra power isn't worth risking your health or your life. Bright surfaces aren't a bargain if they cost you your lungs.

Stay informed, stay safe and let Nature Kleen guide you to truly clean and healthy spaces.