Hydrogen Peroxide is as a safe alternative to chlorine bleach in the laundry and as a household disinfectant. It is non-toxic and rapidly biodegrades.

Hydrogen peroxide vs. chlorine bleach

Like chlorine, hydrogen peroxide is used industrially to bleach paper and textiles and to treat polluted wastewater, and at home to whiten clothes and disinfect surfaces. Unlike chlorine, hydrogen peroxide is commonly sold in a safe, diluted form and is not an environmental pollutant.

Hydrogen peroxide can be toxic in high concentrations, such as those used for industrial processes, or if swallowed in large doses. However, hydrogen peroxide is safe to use as a mouthwash and antiseptic in the low concentrations found in household bottles. By contrast, chlorine bleach is a strong irritant on the skin and respiratory system and can be toxic.

How does hydrogen peroxide work?

Most living organisms have an enzyme called catalase. When hydrogen peroxide comes into contact with catalase in a blood, wine or yellow armpit stains, for example, it causes a reaction that breaks hydrogen peroxide (H2O2) into pure water (H2O) and oxygen (O2). This release of oxygen creates the bubble and fizz that hydrogen peroxide is known for, and is what lifts stains without harming the fabric.

Hydrogen peroxide that is diluted for household use is not as strong as chlorine bleach. As a result, it may not remove stains as quickly as chlorine bleach, but it will also not destroy the fabric’s fibers.  Stubborn stains or dirty clothing and fabrics can be presoaked in hydrogen peroxide before washing. Like other non-chlorine bleaches, hydrogen peroxide is safe to use on colors.

Hydrogen peroxide can also be used as a household disinfectant, though the 3% to 5% concentrations commonly used in homes is not quite as powerful as chlorine bleach at destroying pathogens. Hydrogen peroxide is sometimes used alongside vinegar to boost the disinfecting capabilities of both ingredients. While hydrogen peroxide and vinegar are each safe on their own, mixing them can be harmful. Their combination produces a highly effective disinfectant called peracetic acid, which (like chlorine bleach) is a severe irritant and can be toxic in high concentrations and prolonged exposure.

How to use hydrogen peroxide

To lift stains, dab hydrogen peroxide directly on the stain with a cotton swab or clean white cloth and let it soak for 15 minutes or more, depending on the stain. Check colored clothing often to make sure the direct application of hydrogen peroxide does not lighten the fabric. You can test the colorfastness of a fabric by leaving a small amount of hydrogen peroxide on a hidden area for at least 15 minutes.

To brighten laundry - both whites and colors - add half a cup of hydrogen peroxide to the washing machine along with your regular detergent.

Hydrogen peroxide can be found in a brown bottle in the first aid section of the supermarket or drugstore. It slowly degrades once it has been exposed to air, so open bottles have a shelf-life of two years.