Aluminum Chlorohydrate is a highly effective inorganic salt primarily utilized as an antiperspirant active to reduce sweat production. It functions by forming temporary, superficial gel plugs within sweat ducts to provide long-lasting moisture control and secondary odor reduction.
- INCI Name:
- Aluminum Chlorohydrate
- Chemical/Scientific Name:
- Aluminum chlorohydroxide
- Common Aliases:
- Hydroxyaluminum chloride, Basic aluminum chloride
| Category: | Active Substances |
| Source Origin: | Synthetic |
| Comedogenic Rating: | 0 |
| Primary Industries: | Personal Care, Water Treatment |
| Solubility: | Soluble in Aqua and ethanol |
At a Glance: Properties & Effects
| Sweat Suppression: | |
| Antimicrobial Efficacy: | |
| Irritation Risk: |
Primary Benefits:
- Significantly reduces eccrine and apocrine sweat flow.
- Indirectly limits the growth of odor-causing bacteria by reducing moisture.
- Provides high formula stability in various delivery formats like roll-ons and aerosols.
Potential Risks:
- May cause stinging or localized irritation on freshly shaved or broken skin.
- Can leave white residues on clothing if not formulated with adequate emollients.
Biological Action & Cosmetic Profile
The primary mechanism of action involves a pH-dependent polymerization process. Upon contact with sweat, which has a higher pH than the product itself, Aluminum Chlorohydrate undergoes a chemical transition to form a polymeric Aluminum Hydroxide gel. This gelatinous substance creates a physical plug within the distal end of the sweat duct, known as the acrosyringium. By obstructing the duct, it prevents the secretion of sweat onto the skin surface.These plugs are strictly temporary and superficial. Normal physiological processes, such as the natural desquamation of skin cells and regular washing, ensure the plugs are removed within 24 to 48 hours. Beyond moisture control, the reduction in sweat alters the local microenvironment, making it less hospitable for the bacteria responsible for body odor.Dermatological formulations often incorporate this salt in aqueous solutions or anhydrous sticks. In the presence of Alcohol Denat, the ingredient dries rapidly, enhancing user convenience. Formulators frequently add humectants like Glycerin to mitigate potential dryness or irritation associated with the astringent nature of the salt.
Broader Applications & Origins
While most recognized for its role in personal hygiene, this compound serves critical functions in industrial water purification. It acts as a coagulant, binding to microscopic impurities to facilitate their removal through filtration. In the cosmetic realm, it is manufactured through the reaction of aluminum with hydrochloric acid, resulting in a complex of aluminum polymers that are more stable and less acidic than traditional aluminum chloride.
Routine Integration
Synergies:
- Silica: Enhances the dry-touch feel and improves the glide of stick formulations.
- Allantoin: Helps soothe the skin and counteract potential irritation from the acidic nature of antiperspirant salts.
- Talc: Often used in powders to provide immediate tactile dryness while the active salt begins its action.
Conflicts:
- Freshly Shaved Skin: Avoid application immediately after hair removal to prevent acute follicular irritation.
- Severe Eczema: Should be used with caution on compromised barriers where the astringent effect may exacerbate dryness.
Clinical Consensus & Safety
The Scientific Committee on Consumer Safety (SCCS) released a definitive opinion in 2020 (SCCS/1613/19) confirming the safety of Aluminum Chlorohydrate in cosmetic products. Systematic reviews indicate that dermal absorption is extremely low, estimated at approximately 0.01%, meaning very little aluminum enters the systemic circulation. Extensive clinical evidence from the Cosmetic Ingredient Review (CIR) and various peer-reviewed studies has found no causal link between the use of aluminum-based antiperspirants and the development of breast cancer or Alzheimer’s disease.
Is Aluminum Chlorohydrate safe for daily use?
Yes, clinical data and regulatory bodies like the SCCS confirm it is safe for daily topical application. The low absorption rate ensures it remains on the skin’s surface or within the superficial ductal layer rather than entering the bloodstream in significant amounts.
Does it block pores permanently?
No, the plugs formed are temporary. They are naturally expelled as part of the skin’s regular cell turnover process or washed away during bathing.
What is the difference between this and aluminum chloride?
Aluminum Chlorohydrate is a larger, more complex molecule that is less acidic and significantly less irritating than aluminum chloride. This makes it better suited for daily-use commercial antiperspirants, whereas aluminum chloride is typically reserved for clinical-strength treatments for hyperhidrosis.