Household Chemicals You Should Never Mix

Chemicals You Should Never Mix
Most of the household chemicals you should never mix include cleaners and disinfectants. Always consult product labels before combining chemicals.

Household chemicals help with cleaning, disinfection, pest control, and more, but there are some chemicals you should never mix. The results can injury you, make you sick, or even cause a fatality. Do not mix these common household chemicals.

Bleach + Ammonia = Chloramine

Really, just don’t mix bleach with any household product unless the label states that it’s safe. Bleach and ammonia are a particularly nasty mixture because they react and form chloramine vapor. Chloramine has that “swimming pool” odor and irritates your eyes, respiratory system, and skin. Other results of the reaction include hydrochloric acid, hydrazine, and chlorine gas. All of these are toxic.

This mixture presents the most common accidental hazard because many cleaners contain one chemical or the other. Bleach occurs in bathroom products, some laundry detergents, and other cleaners, while ammonia is in glass cleaner, furniture polish, multi-surface cleaners, and some floor cleaners.

Another route of accidental exposure is cleaning a pet litter box using bleach. Urine decomposes into ammonia. Play it safe and thoroughly rinse out the litter box using water before disinfecting with bleach.

Bleach + Alcohol = Chloroform

Mixing bleach with alcohol makes chloroform. Chloroform is an anesthetic, so it can cause unconsciousness. If the concentration is high enough, it even causes death. Exposure does not do your liver any favors either. Other toxic products include hydrochloric acid and dichloroacetate.

Bleach reacts with any alcohol, but the most common mixture involves bleach and rubbing alcohol or isopropyl alcohol. One common accidental exposure comes from using alcohol-based hand sanitizer and bleach. Also, take care using disinfecting sprays or toilet bowl cleaner around bleach.

Bleach + Vinegar = Chlorine Gas

Bleach reacts with any acid and makes chlorine gas. Vinegar contains dilute acetic acid, so mixing bleach and vinegar releases chlorine. Chlorine has a strong odor. It attacks skin, eyes, and the respiratory system, causing chemical burns, coughing, vomiting, and potentially death. Chlorine reacts with water in the lungs, forming hydrochloric acid and worsening the situation.

Combining the two products is tempting, because the reaction boosts cleaning power. But, the health hazard outweighs the potential benefit. The safe way of cleaning using both bleach and vinegar is rinsing with water before switching between the two products. Never mix oven cleaners, stain removers, or drain cleaners with each other or with bleach or vinegar, unless the label states it’s safe.

Hydrogen Peroxide + Vinegar = Peracetic Acid

Household hydrogen peroxide and vinegar are two chemicals you should never mix because they react and form peracetic acid and peroxyacetic acid. These acids are highly corrosive and cause chemical burns.

Other Household Chemicals You Should Never Mix

While mixing bleach with pretty much anything is bad and mixing peroxide with acid is dangerous, there are other common household chemicals you should never mix. In these cases, the reason has less to do with safety and more to do with effectiveness.

  • Mixing baking soda and vinegar neutralizes the two chemicals. It makes a great chemical volcano, but is fairly useless as a cleaning combination.
  • Combining a retinol or retinoid face product with either alpha-hydroxy acid (AHA) or glycolic acid wastes money because retinol needs a certain pH level to work. The acids make skin too acidic, so you lose wrinkle-fighting power. You can use both products, but either let one absorb completely before applying the other or else alternate days of use.
  • Bleaching or coloring hair previously colored using a henna dye is a stylist’s nightmare. The reason is that henna isn’t just ground-up plant material. The formulation typically contains other chemicals, such as metal salts and strong bases. Peroxide in hair bleach or dye developer reacts with these other chemicals. Possible outcomes include a skin reaction and a chemical burn. There’s a good chance of hair breaking or even falling out. What color you get is anyone’s guess.

What to Do If You Mix Chemicals You Should Never Mix

Accidents happen, so know what to do if you mix chemicals and they react.

  • Open windows and increase ventilation before a cleaning session.
  • Wear gloves to protect your skin from irritation and burns.
  • If you smell any noxious odors, remove yourself from the situation until the vapors clear.
  • Seek medical attention if you feel nauseous or short of breath. Call Poison Control or chat online at


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