What are carbomers? Uses, risks and environment

Carbomers are synthetic ingredients that many companies use in their products due to their suspending, emulsifying and thickening properties.

Carbomer is the trade name for polyacrylic acid. Companies use it widely in formulations for several industries, including cosmetics, pharmaceuticals, and personal care.

Carbomers are cross-linked synthetic polymers of high molecular weight acrylic acid. Dried carbomers are light, white powders. However, people frequently use them in the form of gels or liquids.

A person can find them in a wide range of products, including:

  • shampoos
  • lotions
  • nail polish
  • cuticle removers
  • face masks
  • Styling gel
  • Solar cream
  • lipstick
  • acne treatment gels
  • moisturizers
  • detergent
  • floor cleaners
  • surface cleaning fluids
  • paints
  • waterproof and oil resistant coatings
  • printing inks

Manufacturers in all industries make extensive use of carbomers due to their versatility.

Companies mainly use carbomers for:

  • Thickening Formulas: Many manufacturers use carbomers as thickening agents to make formulations more viscous. This helps control the consistency, texture and flow of solutions that contain ingredients with different levels of solubility.
  • Improve texture: Carbomers can also absorb and retain water, swelling up to 1000 times their original size. This can help improve the appearance of formulations, giving them a clear, gel-like consistency. This property is responsible for giving certain gels, creams and lotions their soft and silky texture.
  • Stabilize formulations: Carbomers help suspend and distribute insoluble solids – which cannot dissolve – in the liquid. They also prevent the oil and liquid parts of a formulation from separating. This property helps to stabilize the products, so that they achieve a longer shelf life.

The pharmaceutical industry also uses carbomers in various ways:

  • as a bioavailability enhancer, controlling the release of drugs so the body can easily absorb them
  • as a bioadhesive to adhere formulations to skin and mucous membranes
  • to create a wide range of viscosity and flow in gels
  • permanently suspend certain ingredients in oral suspensions and topical medications

People can find carbomers in products intended for parts of the body, including the eyes, mouth, intestines, nose, vagina, and rectum. Pharmaceutical companies can use carbomers in products such as tablets, transdermal patches and creams.

The Food and Drug Administration (FDA) has approved many carbomers for use as inactive ingredients in pharmaceuticals.

Additionally, the Environmental Working Group (EWG) considers carbomer safe for use in cosmetics and personal care.

The Cosmetic Ingredient Review (CIR) Expert Committee has also stated that carbomers are safe to use in cosmetics based on their current use and concentration.

An assessment by the CIR Expert Panel also noted that carbomers present a low potential risk of allergenicity through photocontact and phototoxicity.

A study in rabbits demonstrated that carbomers also have a low potential risk of sensitization and skin irritation, even at high carbomer concentrations up to 100%. The CIR expert panel also found that carbomers had a mildly irritating effect on the eyes of rabbits.

A human study found that the potential risk of sensitization and skin irritation was low with a carbomer concentration of 1%.

However, the CIR expert panel also noted that benzene is an impurity in carbomers. It recommended that manufacturers reduce its concentration to the lowest possible value.

The FDA also recommend that drug manufacturers avoid using benzene during the manufacturing process. Manufacturers must report any cases of benzene contamination to the agency.

Benzene is a known toxic agent that can cause leukemia. It is also toxic to blood cells and can lead to blood disorders. Exposure to benzene can also cause bone marrow failure, which can increase the risk of developing:

Learn more about potential risk factors for AML.

Environmental exposure to benzene can also cause cancer.

While traditional carbomers were typically combined to form large polymer chains (polymerization) using benzene, many modern carbomers are synthesized with processes that do not use benzene.

According to the EWG, carbomers are non-toxic and do not bioaccumulate in the environment.

However, some organizations, including the European Chemicals Agency, include carbomers in their lists of microplastics. Other environmental organizations call them liquid microplastics. Microplastics can harm the environment, wildlife and human health. Many environmental agencies define them as pieces of plastic less than 5 millimeters long.

On the other hand, many manufacturers continue to use carbomers and argue that technically they are not microplastics.

The Ethical Consumer Research Association states that carbomers are liquid polymers that do not readily biodegrade.

With this in mind, further conclusive research on the long-term environmental impacts of carbomers and other liquid polymers may be needed.

A person should always follow the manufacturer’s instructions when using a product containing carbomers.

The carbomer name may have links to numbers, such as 934, 940, 941, 971, and 934P, on personal care product labels. These numbers indicate the molecular weight and specific components of the carbomer. It may appear with other names on product labels, such as:

  • Carboxyvinylpolymer
  • Carbopol 910
  • Carbopol 971P
  • Carbopol 981
  • Carbopol ULTREZ 20
  • Pemulen TR-1
  • Pemulen TR-2

It is also important to note that a person can be allergic to carbomers. Before using products containing carbomers, people should perform a skin test to determine if they have any allergies or sensitivities.

Carbomers are a series of polymers derived from acrylic acid. Companies use them in a range of products as emulsifiers, thickeners, suspenders and binders.

Research suggests that they are generally non-irritating to the skin.

Health experts generally consider carbomers to be safe and non-toxic to humans. However, some organizations are expressing concerns about their environmental impact.