Aluminum

What is Aluminum?

Aluminum (Al) is a silvery-white, soft, nonmagnetic metal. Aluminum is the third most abundant element (after oxygen and silicon), and the most abundant metal in the Earth's crust. It makes up about 8% by mass of the crust. Aluminum metal is so chemically reactive that native specimens are rare and it is usually found combined in over 270 different minerals. The chief ore of aluminum is bauxite. 

Aluminum-containing raw materials are used safely and extensively in cosmetics, pharmaceuticals and over-the-counter (OTC) drug products. In cosmetics, they function as pigments and thickening agents. Aluminum compounds also function as active ingredients in OTC drugs such as antacids and antiperspirants. Because aluminum is present in soil, most exposure comes from foods we eat and the water we drink.  Studies demonstrate a negligible potential for Aluminum salts to penetrate the skin. Any small amount absorbed from the use of cosmetic products, would be tiny in comparison to the amounts we consume in the foods we eat daily.
 

How are aluminum-containing ingredients used in cosmetics and personal care products, and how are these uses regulated?

Aluminum-containing ingredients have several uses in cosmetics and personal care products.

Aluminum salts are used as antiperspirants to control sweat.  Antiperspirant ingredients are regulated as over-the-counter (OTC) drugs by the U.S. Food and Drug Administration (FDA).  A manufacturer can only use the aluminum active ingredients that have been approved as safe and effective by the FDA as listed in the OTC antiperspirant monograph. These products can only be used according to the guidelines established in this monograph.

Aluminum may also be present in cosmetic colors.  Aluminum powder is FDA approved and may be safely used in coloring externally applied cosmetics, including cosmetics intended for use in the area of the eye, [21 CFR §73.2645   Aluminum powder.].   In addition, aluminum is a common component in other cosmetic colors where it may be used as a substrate upon which another color is precipitated.  Because the resulting color is not water-soluble, this can prevent ‘bleeding’, for example with lipstick. There are other uses of aluminum-containing ingredients in cosmetics, such as use as thickening agents.  Under federal law, the safety of all ingredients must be substantiated by the manufacturer of the product before it is placed on the market.
 

How do aluminum-containing ingredients function as antiperspirants?

Based on current scientific literature and data, aluminum salts are currently considered a safe and effective means of controlling sweat. In fact, Aluminum salts are the only FDA approved active ingredients for use in antiperspirants.  These salts work by dissolving in sweat and temporarily inhibiting the flow of sweat to the surface of the skin. This reduces the amount of sweat on the skin for a number of hours after the antiperspirant is applied. Aerosol and roll-on antiperspirants products typically contain ACH (Aluminum Chlorohydrate), whereas sticks, gels and other solid products are most likely to contain an Aluminum salt referred to as AZAG (Aluminum Zirconium Tetrachlorohydrex GLY). 

In the European Union (EU), aluminum zirconium chloride hydroxide complexes and the aluminum zirconium chloride hydroxide glycine complexes are permitted within certain concentration limits for use in antiperspirant products, per Annex III of the Cosmetics Directive.

Learn more about the regulations for the use of aluminum-containing ingredients in cosmetics and OTC drugs
 

Safety Information

Aluminum is the third most naturally abundant element in the environment, found in food, water, and pharmaceuticals, as well as a wide range of consumer products.  The safety of antiperspirants that contain aluminum salts is supported by an extensive amount of scientific data.  Antiperspirants are regulated by FDA as over-the-counter (OTC) drugs. As such, they must be shown to be safe and effective and must comply with all other requirements listed in the FDA's OTC antiperspirant monograph.  Individual antiperspirant active ingredients are reviewed for safety by FDA, and only those that are on FDA's monograph approved list may be used in antiperspirant products marketed in the U.S. In fact, Aluminum salts are the only active ingredients that are approved by FDA for use in antiperspirants.  

Product safety of OTCs is also assured though strict adherence to the principles of Quality Assurance (QA) and Good Manufacturing Practices (GMPs). This includes testing the compatibility of the OTC product with packaging as well as shelf-life stability.  In addition, the safety of products is monitored in the marketplace through the reporting of consumer comments. Companies include a phone number on their products where comments may be reported.

Antiperspirants are designed to work on the surface of the skin, and so the products would not work if there was a significant amount absorbed. The amount of aluminum absorbed through the skin from antiperspirants is significantly less than average daily exposure from food and water. One study (1) showed that only 0.012% of the aluminum applied to the underarms was absorbed through the skin, which is much lower than the percentage of aluminum typically absorbed by the gut from food. This study clearly demonstrated that use of an aluminum-containing antiperspirant is not a significant contribution to the body burden of aluminum.  If any small amount was absorbed, this would be tiny in comparison to the amounts we consume in the foods we eat daily. 
 

Urban Legends & Myths

During the 1960s and 1970s, aluminum emerged as a possible suspect in causing Alzheimer’s disease. This suspicion led to concerns about everyday exposure to aluminum through sources such as cooking pots, foil, beverage cans, antacids and antiperspirants.  The ‘aluminum hypothesis’ was first put forward in 1965 when it was shown that the injection of aluminum compounds into rabbits caused tangle-like formations in nerve cells (reference 2). However, these experimental tangles differ in structure and composition from the tangles that are found in the brains of Alzheimer’s patients.  Since then, numerous studies have failed to confirm any role for aluminum in causing Alzheimer’s.  Few experts believe that everyday sources of aluminum pose any threat.

Scientific experts and research bodies, including the Alzheimer's Association and FDA, have concluded that at the present time, there is no evidence that convincingly demonstrates a link between aluminum and Alzheimer’s disease. 

There also have been rumors on the Internet and in the popular press claiming that antiperspirants may be linked to breast cancer. Some of these have suggested a role for aluminum, while others have focused on other areas. Leading cancer research organizations have stated that there is no plausible biological mechanism by which antiperspirants could cause breast cancer. The National Cancer Institute (NCI) has said that “no conclusive research” links antiperspirants and the subsequent development of breast cancer, though the NCI observed that the results of some studies suggest that additional research is needed.  A study reported in the Journal of the National Cancer Institute (JNCI) on October 16, 2002, conclusively debunks the rumor circulating on the Internet which falsely states that antiperspirant use causes breast cancer. Researchers from the Fred Hutchinson Cancer Research Center and the University of Washington conducted an extensive population-based case-control study. They concluded that “These findings do not support the hypothesis that antiperspirant use increases the risk for breast cancer.” Furthermore, according to the American Cancer Society, there have been many extremely thorough epidemiological studies of breast cancer risk and they have not found antiperspirant use to be a risk factor for breast cancer, much less the “leading cause” of the disease. 

FDA now requires all antiperspirant products to include a warning statement that advises people with kidney disease to consult a physician before using the product. Since the kidneys play a large role in eliminating aluminum from the body, FDA decided it was prudent to alert consumers who have some kidney function impairment to the fact that their exposure to aluminum from use of antiperspirants might need to be discussed with their doctor. A panel of kidney disease specialists was set up in conjunction with the American Society of Nephrology to review the FDA recommendation and they offered the following additional perspective:  “Kidney disease” is a non-specific term that is used to describe a broad range of kidney dysfunctions. In general, the new warning statement is meant for kidney disease patients who are on an aluminum-restricted diet and who may not be able to excrete the low levels of aluminum in the body that may result from antiperspirant use. 

The National Kidney Foundation agrees and has stated that “This warning is only meant for people whose kidneys are functioning at 30% or less (also known as Stage 4 or 5 chronic kidney disease – CKD). In reality, it's almost impossible to absorb enough aluminum through the skin to harm the kidneys.”
 

References:

1 - Flarend et al., Food Chem Toxicol. 2001 Feb;39(2):163-8 
2 - Wisniewski, H.M., Terry, R.D., Peña, C., Streicher, E., Klatzo, I. Experimental production of neurofibrillary degeneration. J. Neuropath. & Exp. Neurol., 1965, 24: 139. 

Learn more about Antiperspirants and Deodorants