Bentonite

What Is It?

Aluminum Silicate, Calcium Silicate, Magnesium Aluminum Silicate, Magnesium Silicate, Magnesium Trisilicate, Sodium Magnesium Silicate, Zirconium Silicate, Attapulgite, Bentonite, Fuller’s Earth, Hectorite, Kaolin, Lithium Magnesium Silicate, Lithium Magnesium Sodium Silicate, Montmorillonite, Pyrophyllite and Zeolite are all clay-like ingredients that are based on silicates. In cosmetics and personal care products, these seventeen ingredients are used in a wide variety of product types, including bath products, makeup and skin care products.

Why Is It Used?

The following functions have been reported for these ingredients.

  • Abrasive – Aluminum Silicate, Magnesium Trisilicate, Zirconium Silicate, Attapulgite, Fuller’s Earth, Montmorillonite
  • Absorbent – Aluminum Silicate, Calcium Silicate, Magnesium Aluminum Silicate, Magnesium Silicate, Magnesium Trisilicate, Attapulgite, Bentonite, Fuller’s Earth, Hectorite, Montmorillonite, Pyrophyllite, Zeolite
  • Anticaking agent – Aluminum Silicate, Magnesium Aluminum Silicate, Magnesium Silicate, Magnesium Trisilicate, Fuller’s Earth
  • Binder – Sodium Magnesium Silicate, Lithium Magnesium Silicate
  • Bulking agent – Aluminum Silicate, Calcium Silicate, Magnesium Silicate, Magnesium Trisilicate, Sodium Magnesium Silicate, Attapulgite, Bentonite, Fuller’s Earth, Hectorite, Lithium Magnesium Silicate, Lithium Magnesium Sodium Silicate, Montmorillonite
  • Colorant – Pyrophyllite Deodorant agent – Zeolite
  • Emulsion stabilizer – Bentonite, Montmorillonite
  • Opacifying agent – Aluminum Silicate, Calcium Silicate, Magnesium Aluminum Silicate, Magnesium Silicate, Magnesium Trisilicate, Zirconium Silicate, Attapulgite, Bentonite, Fuller’s Earth, Hectorite, Montmorillonite, Pyrophyllite
  • Slip modifier – Aluminum Silicate, Magnesium Aluminum Silicate, Magnesium Silicate, Magnesium Trisilicate
  • Suspending agent – nonsurfactant – Bentonite, Hectorite
  • Viscosity increasing agent – aqueous – Magnesium Aluminum Silicate, Magnesium Silicate, Magnesium Trisilicate, Attapulgite, Bentonite, Hectorite, Lithium Magnesium Silicate, Lithium Magnesium Sodium Silicate, Montmorillonite

Scientific Facts

Many silicates occur naturally and are mined; others are produced synthetically. The common aspect of all these clay-like ingredients is that they contain silicon, oxygen, and one or more metals. All silicates, especially the clays, have a great ability to absorb water.

Safety Information

The Food and Drug Administration (FDA) has approved Pyrophyllite as a color additive exempt from certification. Pyrophyllite is allowed to be used as a color in externally applied cosmetics and personal care products and drugs if it conforms to FDA specifications. It is not allowed to be used in products intended for the lips or the eye area. The Food and Drug Administration (FDA) has reviewed the safety of Calcium Silicate and Bentonite and determined that they are Generally Recognized as Safe (GRAS) for use as direct food additives (Calcium Silicate at up to 2% of weight of food) and that Kaolin is GRAS for use as an indirect food additive.

Aluminum Silicate is approved for use in polymers with incidental contact with food. Magnesium Aluminum Silicate (antacid), Magnesium Trisilicate (antacid), and Kaolin (skin protectant, anorectal) are used in Over-the-Counter (OTC) drug products. The safety of Aluminum Silicate, Calcium Silicate, Magnesium Aluminum Silicate, Magnesium Silicate, Magnesium Trisilicate, Sodium Magnesium Silicate, Zirconium Silicate, Attapulgite, Bentonite, Fuller’s Earth, Hectorite, Kaolin, Lithium Magnesium Silicate, Lithium Magnesium Sodium Silicate, Montmorillonite, Pyrophyllite and Zeolite has been assessed by the Cosmetic Ingredient Review (CIR) Expert Panel. The CIR Expert Panel evaluated the scientific data and concluded that all seventeen ingredients were safe as used in cosmetics and personal care products.

CIR Safety Review:

The CIR Expert Panel determined that the data provided in the report were sufficient to assess the safety of Aluminum Silicate, Calcium Silicate, Magnesium Aluminum Silicate, Magnesium Silicate, Magnesium Trisilicate, Sodium Magnesium Silicate, Zirconium Silicate, Attapulgite, Bentonite, Fuller’s Earth, Hectorite, Kaolin, Lithium Magnesium Silicate, Lithium Magnesium Sodium Silicate, Montmorillonite, Pyrophyllite and Zeolite. The CIR Expert Panel noted that issues of safety were similar among these ingredients and were broadly applicable to the two types of ingredients reviewed in the report: the silicates and the silicate clays/clay materials. These ingredients were generally non-irritating to the skin.

Because of their solid particle form, some studies showed that these ingredients were irritating if placed in the eyes. These ingredients were not genotoxic or significantly toxic in oral acute or short-term oral or injection toxicity studies. Occupational exposure to mineral dusts has been studied extensively. Fibrosis and pneumoconiosis have been documented in workers involved in the mining and processing of Aluminum Silicate, Calcium Silicate, Zirconium Silicate, Fuller’s Earth, Kaolin, Montmorillonite, Pyrophyllite and Zeolite.

The CIR Expert Panel concluded that the pulmonary damage in humans was the result of direct occupational inhalation of the dusts. The CIR Expert Panel considers that most formulations containing these mineral ingredients will not be inhaled and of the preparations that have fractions that might be inhaled, the concentration of the ingredient is very low. The CIR Expert Panel considered that any sprays containing these mineral ingredients should be formulated to minimize their inhalation. Susbsequently, the CIR Expert Panel concluded that these ingredients were safe as currently used in cosmetic and personal care formulations. All color additives used in foods, drugs and cosmetics in the United States must be approved by FDA and listed in the Code of Federal Regulations.

In some cases, FDA requires that each batch of color produced for use in regulated products can be used only if it is certified by the agency to meet strict specifications. FDA maintains a laboratory especially for this purpose and color manufacturers must pay a fee to support this activity. FDA only approves colors after extensive review of all safety data and publication of the basis for its approval in the Federal Register.

You can find out more about FDA regulation of colors at: http://www.fda.gov/ForIndustry/ColorAdditives/RegulatoryProcessHistorica…

Link to FDA Code of Federal Regulations for the color uses of Pyrophyllite

For the food uses of Calcium Silicate, Bentonite, Clay (Kaolin) and Aluminum Silicate

 

For the OTC uses for Magnesium Aluminum Silicate, Magnesium Trisilicate, and Kaolin

Bentonite (a Natural Hydrated Aluminium Silicate) is listed in the Cosmetics Directive of the European Union (Annex IV, Part I) as CI 77004, and may be used in all cosmetics and personal care products. When used as a color in cosmetic products in the European Union, this ingredient must be called CI 77004. Aluminum Silicate, Calcium Silicate, Magnesium Aluminum Silicate, Magnesium Silicate, Magnesium Trisilicate, Sodium Magnesium Silicate, Attapulgite, Fuller’s Earth, Hectorite, Kaolin, Lithium Magnesium Silicate, Lithium Magnesium Sodium Silicate, Montmorillonite, Pyrophyllite, and Zeolite may be used in cosmetics and personal care products marketed in the European Union according to the general provisions of the Cosmetics Regulation of the European Union.

EU Cosmetic Regulation

The Joint FAO/WHO Expert Committee on Food Additives did not consider it necessary to specify a daily intake value for the group consisting of Silicon Dioxide, Aluminum Silicate, Calcium Silicate, Calcium Aluminum Silicate and Sodium Aluminosilicate.

 

More Scientific Information

The silicates are typically used as abrasives, opacifying agents, viscosity increasing agents, anticaking agents, emulsion stabilizers, binders and surfactant – suspending agents in cosmetics and personal care products. The clay silicates primarily function as adsorbents, opacifiers and viscosity increasing agents – aqueous. Pyrophyllite is also used as a colorant in externally applied cosmetics and personal care products, as well as externally applied drugs.

Resources

Find out more about the regulation of Over-the-Counter drugs by the Food and Drug Administration

Find out more about the regulation of Food Additives by the Food and Drug Administration