Metallic aluminum, primarily utilized under the colorant index CI 77000, functions as a high-reflectance pigment and opacifying agent in cosmetic formulations. Its primary role involves providing a silver, metallic luster to decorative products while remaining chemically inert on the skin surface.
- INCI Name:
- Aluminum
- Chemical/Scientific Name:
- Aluminum (Elemental)
- Common Aliases:
- CI 77000, Aluminum Powder, Pigment Metal 1
| Category: | Colors |
| Source Origin: | Mineral-derived/Synthetic |
| Comedogenic Rating: | 0 |
| Primary Industries: | Color Cosmetics, Personal Care, Pharmaceuticals |
| Solubility: | Insoluble |
At a Glance: Properties & Effects
| Texture Enhancement: | |
| Formula Stability: | |
| Irritation Risk: |
Primary Benefits:
- Provides intense metallic reflectance and “frost” finishes in makeup.
- Increases the opacity of formulations, allowing for better coverage.
- Acts as a stable colorant that does not bleed or migrate in anhydrous systems.
Potential Risks:
- Potential for inhalation if used in loose powder formats (rare for this particle size).
- Physical abrasion if particles are not properly milled or coated.
Biological Action & Cosmetic Profile
Metallic aluminum particles are fundamentally different from soluble aluminum salts used in antiperspirants. When utilized as a pigment, the metal is processed into microscopic flakes that are significantly larger than the pores of the skin. Because these particles are insoluble in both water and oil, they remain entirely on the surface of the stratum corneum rather than undergoing dermal absorption. The optical properties of this element stem from its ability to reflect nearly all visible light that hits its surface. Formulators often combine it with other minerals like Mica or Silica to create multi-dimensional shimmer or to adjust the “slip” of the final product. In the context of the skin barrier, the material is biologically inert, meaning it does not trigger cellular pathways or interfere with natural lipid production.Structural integrity within a formula is another key attribute of this metal powder. Unlike many organic dyes, it is highly resistant to light degradation and does not react with common cosmetic preservatives or emollients. This stability ensures that the visual appearance of the product remains consistent throughout its shelf life, even when exposed to UV radiation.
Broader Applications & Origins
While widely recognized for its use in nail polishes and eye shadows, this material also serves functional roles in packaging and protective coatings. Most cosmetic-grade aluminum is produced through a vapor deposition process or high-energy milling to ensure uniform particle shape and size. In pharmaceutical contexts, it is sometimes used as a substrate for “lakes” (pigments precipitated with a metal salt) to ensure color consistency in tablet coatings.
Routine Integration
Synergies:
- Titanium Dioxide: Enhances the brightness and coverage of metallic pigments.
- Dimethicone: Provides a smooth vehicle for even distribution of metallic flakes across the skin.
- Iron Oxides: Used in combination to create bronze, copper, or gold tones.
Conflicts:
- Strong Acids/Bases: Extremely high or low pH levels can cause the metal to oxidize or release hydrogen gas, though this is rare in finished consumer skincare.
Clinical Consensus & Safety
The Scientific Committee on Consumer Safety (SCCS) and the Cosmetic Ingredient Review (CIR) Expert Panel have both concluded that aluminum in its metallic and insoluble forms is safe for use in cosmetic products. Systematic reviews, including the 2023 SCCS updated opinion, emphasize that dermal absorption of aluminum from cosmetic products is extremely low (approximately 0.01%). Clinical data indicates no correlation between the topical application of aluminum-containing cosmetics and systemic toxicity, as the skin barrier effectively prevents the entry of metallic particles into the bloodstream.
Does aluminum in makeup cause health issues?
Current clinical evidence from the SCCS indicates that aluminum in cosmetics does not penetrate the skin in significant quantities. The metallic powder used as a colorant is considered inert and does not pose a risk to systemic health when applied topically.
Is this the same as the aluminum in antiperspirants?
No. Aluminum powder (CI 77000) is the elemental metal used for color. Antiperspirants use aluminum salts, such as aluminum chlorohydrate, which are soluble and designed to temporarily plug sweat ducts. They function through different chemical mechanisms.
Can aluminum clog pores?
Metallic aluminum has a comedogenic rating of 0. Because it is an inorganic, insoluble mineral flake, it sits on the surface of the skin and does not sink into the pores or trigger sebum blockages.