12 Household Cleaner Combinations You Should Never, Ever Mix

When faced with a big (and gross) mess at home, it’s tempting to throw every cleaning product you’ve got at the problem. But don’t! Most cleaning products are plenty effective on their own. And when you combine some of them — such as vinegar and hydrogen peroxide — it can not only be toxic, but also lethal in some cases.

“Some people just think more product is better, but they don’t think about science and safety first,” says Nancy Bock of the American Cleaning Institute. “Mixing cleaning products can lead to irritated airways, respiratory problems, or burns to skin, eyes, throat, nose, and lungs. Some gasses created from combined cleaning products could cause damage [to] the nervous system, eyes, lungs, skin, liver, kidneys, and even death.”

Mixing cleaners can be risky for several reasons, says Rocky Vuong, founder and owner of Calibre Cleaning in Melbourne, Australia. “Mixing cleaning products can lead to a reduction in their effectiveness or even create new, potentially harmful substances,” he adds.

So, a good rule of thumb: “Don’t take any chances when it comes to safe use of products,” says Bock. Don’t believe us yet? Here are some tempting cleaning combos that are especially bad.

While these two chemicals can be used in succession as a cleaning duo, do not mix them together. “Combining these two creates peracetic acid or corrosive acid, an irritant that, in high concentrations, can harm the skin, eyes, throat, nose, and lungs,” says Bock.

If you’ve got a clog, it’s tempting to pour in as much drain cleaner as you can find under your sink — but beware of using one right after the other, because these super-strong formulas (they’re meant to eat away those clogs!) can react very, very badly. “Combining drain cleaners can cause the release of chlorine gas and potentially lead to an explosion,” says Bock.

Combining bleach and ammonia releases chloramine vapors, which can cause respiratory problems and throat burns if inhaled, says Bock. Beware that many cleaning products contain either bleach or ammonia in their formulas, so the fact that you could be combining these two might not be so obvious — which is why you should never, ever mix any kind of cleaning product.

This combination releases chloroform, a gas notorious for being used by old-fashioned bad guys to knock out their victims. High levels of exposure can lead to damage of the nervous system, eyes, lungs, skin, liver, kidneys, and even death. “Even low levels can make you dizzy or nauseous,” says Bock.

Same deal: This releases chlorine and chloramine vapors. These can cause a chemical burn, most likely in your lungs or eyes,” says Bock.

They may be super effective on their own, but Lysol and bleach together can create toxic chloramine fumes — a chemical variant of chlorine — which Vuong says can lead to respiratory problems or eye irritation. 

Glass cleaner (such as Windex) typically contains ammonia, which should never be mixed with bleach. According to Vuong, the combo can create toxic chloramine fumes, similar to the Lysol and bleach combination. 

While some detergents are compatible with bleach — after all, many people do laundry with both bleach and laundry soap — others may contain ammonia or other not-safe ingredients that can create harmful fumes. “Always check the labels before mixing,” says Vuong. 

Pine-Sol is generally safe to mix with most laundry detergent, but be cautious with detergents containing bleach or ammonia, as Vuong says this can create harmful fumes (or simply reduce the effectiveness of both products). 

Fabuloso contains surfactants and fragrances that aren’t safe to mix with bleach. The combo, Vuong says, could create harmful fumes and damage surfaces, due to the high pH levels. 

Another potentially risky combo is ammonia and vinegar, which creates a high-pH solution that can cause skin irritation or burns. “Additionally, the combination can produce an unpleasant odor,” Vuong says. 

Mixing dish soap with bleach can create toxic chloramine fumes if the dish soap contains ammonia, so Vuong recommends always checking the labels before mixing. 

The takeaway: Again, to be super clear, you should never mix cleaning supplies! It’s that simple.