Chemical Profile: Chlorine Bleach

Chemical Profile Artificial Colors MADE SAFE Blog

Why It Matters

What often gives paper towels, toilet paper, and feminine care products their white color? The answer is chlorine bleach.

Chlorine bleach is widely used by households, businesses, and medical facilities for its ability to disinfect surfaces or whiten fabrics and materials like paper. It is also used to kill pathogens in swimming pools or to treat wastewater and therefore is a prevalent contaminant in drinking water. The interactions between chlorine bleach and other constituents in aquatic environments can result in the formation of harmful by-products, not to mention, chlorine bleach is toxic to aquatic life. Finally, chlorine bleach is linked to asthma.

While chlorine bleach can be useful in curbing the spread of disease in medical facilities, it is a serious disinfectant that is not necessary for most typical cleaning scenarios. 

What Is It?

Sodium hypochlorite, or chlorine bleach, is a chlorinated inorganic disinfectant and antimicrobial agent commonly used in household cleaning products to kill bacteria, fungi, and viruses or to whiten or brighten fabric. In 1957, it was registered for use as a pesticide. [6]  Household bleach may contain up to 10% sodium hypochlorite, while industrial bleaches have higher concentrations of up to 50%. [5]

Chemical Profile Chlorine Bleach MADE SAFE Blog

Where It's Found

Chlorine bleach is found in cleaning products or is used in isolation with the purpose of disinfecting surfaces. It can also be found in laundry detergents and treatments as a stain “removal” and whitening agent. It is used in swimming pools, drinking water, and other water and wastewater systems. It is even used to treat various crops, seeds, and/or soil and for turning certain items white, such as period care products and other toiletries, or in treating wood pulp to create white paper.

The Health Concern

Chlorine bleach is acutely toxic for being corrosive. It can cause severe skin burns and eye damage and is toxic to aquatic life. [1] 

Toxicity via inhalation is primarily due to the gases that result from mixing chlorine bleach with acidic compounds. Under normal conditions, significant amounts of chlorine gas are not emitted from sodium hypochlorite. When chlorine bleach is mixed with acidic cleaning agents, it releases chlorine gas. If mixed with ammonia-based cleaning agents, it releases chloramine compounds, both of which are respiratory irritants, and in extreme cases, can cause death. [4][5]

When chlorine bleach enters aquatic environments, the release of free chlorine reacts with natural organic matter to form potentially harmful disinfection by-products. The by-product that forms is dependent on various physical environmental factors, in addition to the type of organic and/or inorganic matter present in the reaction. These by-products can fall into chemical classes that are potential carcinogens, developmental and reproductive toxicants, or may interfere with or damage DNA. It is also possible for disinfection by-products to contaminate soils and groundwater. [3]  Notably, chlorine bleach in wastewater can form trihalomethanes, a potential carcinogen, which subsequently contaminates drinking water. [3] 

Chlorine bleach in cleaning products can even react with the other ingredients (e.g., surfactants, fragrances, etc.) in the product to form halogenated volatile organic compounds (VOCs). VOCs can also be emitted from the reaction of chlorine bleach with organic matter on dirty surfaces it is used to clean. [2]  Halogenated VOCs are linked to various adverse health effects, and some are potential carcinogens.

Other by-products of chlorine bleach include  dioxins . Dioxins are formed from chlorine bleaching processes used to treat wood pulp to make white paper or for turning period products and other toiletries white. Dioxins are linked to cancer, reproductive toxicity, and hormone disruption.

Finally, chlorine bleach is linked to asthma. It is considered an asthmagen, a substance that can cause asthma.  [7]  It is also recognized as an asthma trigger, which means it can trigger an asthma attack in those that already have asthma.  [8]


As part of the 360° Ecosystem Approach Screening, MADE SAFE evaluates the ingredients used at all stages of a product’s life cycle, from its manufacture to its final formulation. As such, chlorine bleach is not permitted as a treatment or cleaning agent in any MADE SAFE Certified products. This means not only that MADE SAFE products will not include chlorine bleach as a product ingredient you would find listed on a label, but also that the chemical will not be utilized in any step of the materials and manufacturing process. 

How to Avoid It

Avoid using chlorine bleach when possible. If you must use bleach, try to limit its usage for scenarios when a serious disinfectant is necessary. Otherwise, cleaning or sanitizing surfaces with safer alternatives is best. For a quick and easy DIY household cleaner that’s safe and effective, combine one part filtered water to one part distilled white vinegar.

For safer cleaning when you can’t avoid it:

  • · Wear gloves and eye protection when handling chlorine bleach or other bleach products.
  • · Dilute chlorine bleach with water to limit the amount of exposure. Follow instructions on the bottle for preparing dilutions, or use the CDC’s recommendations for preparing dilutions if bottle instructions are not available to you.
  • · Never mix bleach with any other cleaning products and avoid buying bleach cleaners that contain other inactive ingredients, like surfactants or fragrances.
  • · Shop MADE SAFE Certified cleaning products and period care products.


[1] ECHA European Chemicals Agency. (2022). Sodium hypochlorite. Accessed February 12, 2023. Retrieved from

[2] Odabasi, M. (2008). Halogenated Volatile Organic Compounds from the Use of Chlorine-Bleach-Containing Household Products. Environ. Sci. Technol., 42, 1445-1451.

[3]  Parveen, N., Chowdbury, S., Goel, S. (2022). Environmental impacts of the widespread use of chlorine-based disinfectants during the COVID-19 pandemic. Environmental Science and Pollution Research, 29, 85742-85760.

[4]  Pascuzzi, T.A. and Storrow, A.B. (1998). Mass Casualties from Acute Inhalation of Chloramine Gas. MILITARY MEDICINE, 163(2), 102-104.

[5] Public Health England. (2015). Sodium Hypochlorite Toxicological Overview. Retrieved from Sodium Hypochlorite Toxicological Overview

[6] United States Environmental Protection Agency (EPA). (1991). R.E.D. Facts Sodium and Calcium Hypochlorite Salts. Retrieved from  

[7] Association of Occupation and Environmental Clinics (AOEC). (ND). R.E.D. Exposure Code Lookup. Retrieved from  

[8] United States Centers for Disease Control and Prevention (CDC). (2022). Common Asthma Triggers. Retrieved from  

If you found this post valuable, please share it below. Follow us on social to let us know what you like, what you need, and what you want to see more of. Also, don’t forget to ask the companies making your favorite products to become #MADESAFE Certified. Remember, your voice matters!

Back to blog