About Aluminium and Antiperspirants
Lise
Today we're looking at a popular antiperspirant ingredient that has (understandably) caused both confusion and concern in many.
The ingredient is aluminium chlorohydrate.
Let's start with the first part of that name: aluminium (spelled as aluminum and aluminium but it's the same substance).
Aluminium is Everywhere
Aluminium is the third most naturally abundant element in the environment (after oxygen and silica). It is present almost everywhere – in food and water as well as all kinds of consumer products.
Aluminium is mined from bauxite ore. We can thank the French geologist from Les Baux – Pierre Berthier – for discovering that aluminium was predominant in this ore in 1821 (and I know you've already guessed why the ore is named bauxite). Bauxite is fairly easily mined because it is almost always found near the surface of the terrain.
Aluminium Compounds
Aluminium is more than the metal we all know as packaging, foil wrapping, metal siding, and framework for light structures. It is also available in other forms, such as aluminium salts (or compounds).
Aluminium compounds are a water-soluble group of aluminium complexes, and aluminium chlorohydrate is composed of hydrochloric acid, water, and aluminium.
Aluminium compounds are commonly found in commercial antiperspirants. (REF) and one of the most commonly used is our star ingredient today: aluminium chlorohydrate.
How Aluminium Salts Work in Antiperspirants
Aluminium salts are quite effective antiperspirants and work in 2 ways:
By reacting with the electrolytes in sweat. This reaction causes a gel-like substance to form and plug the duct of the sweat gland. The plug prevents the gland from excreting sweat until the natural sloughing off of skin cells under the arms removes it.
By interacting with the keratin fibrils (read: very fine fibers) in the sweat ducts – again forming a plug that prevents sweat from reaching the surface of the skin.
While it is an excellent antiperspirant, the concerns about this ingredient have been from fear of absorbing it through use.
What Science Says about Aluminium Chlorohydrate Absorption
In 2001, aluminium chlorohydrate absorption was tested and the study concluded:
"Results indicate that only 0.012% of the applied aluminium was absorbed through the skin. At this rate, about 4 microg of aluminium is absorbed from a single use of ACH (aluminium clorohydrate) on both underarms. This is about 2.5% of the aluminium typically absorbed by the gut from food over the same time period. Therefore, a one-time use of ACH applied to the skin is not a significant contribution to the body burden of aluminium." (REF)
This sounds promising doesn't it?
I thought so too at first – especially since this study has been quoted numerous times.
But let's look at what the Scientific Committee on Consumer Safety (SCCS) had to say after examining it in detail:
"The shortcomings of this study are that it was not done in accordance with good practice (GCP) and it was performed using only 2 volunteers." (REF)
Testing only a one time application on only two volunteers?
Hmmm.
Most folks who use antiperspirants use them daily - not just one time. And 2 people doesn't seem like a representative group, does it?
The Journal of Inorganic Biochemistry published an article entitled Aluminium, antiperspirants and breast cancer in 2005 that stated:
"Aluminium is known to have a genotoxic profile, capable of causing both DNA alterations and epigenetic effects, and this would be consistent with a potential role in breast cancer if such effects occurred in breast cells". (REF)
The article continues:
"the effects of widespread, long term and increasing use remains unknown" (REF)
Find the full article here
If you go digging around bit, you'll find there are numerous studies and papers to be found on this topic. As it happens, the SCCS has examined a great number of them and in 2014 concluded the following about absorption of aluminium through skin:
"The available studies are of poor quality and have not been carried out according to the current requirements. In the absence of any better data to estimate skin penetration of aluminium, the SCCS considers that aluminium absorption after dermal exposure is still very poorly understood. A conclusion on internal exposure to aluminium following cosmetic use cannot be drawn." (REF)
And finally:
"The authors conclude that these observations do not formally identify aluminium as a breast carcinogen, but challenge the safety ascribed to its widespread use in underarm cosmetics."
Find the full paper here.
In May of 2022, the SCCS submitted their latest assessment, Safety of Aluminium in Cosmetics - Submission III which concluded the following
"The SCCS considers that aluminium compounds are safe when used
a. in non-sprayable product categories at the maximum levels indicated in Table 4;
and
b. in sprayable antiperspirant products, provided that the maximum percentage of particles with 10 μm diameter does not exceed 20% of the total aerosolised particles
The SCCS could not assess safety of aluminium compounds in sprayable applications other than antiperspirant."
They were also asked to consider safety levels when aluminium exposure came from a combination of sources and offered the following conclusion:
"The aggregate exposure to aluminium from cosmetic and non-cosmetic sources may exceed safe limits."
In short, there is no clear answer. Tallying up the combined exposure from food, pharmaceuticals and cosmetics may exceed safe levels of exposure.
Find more and download the SCCS submission here.
It (still) looks like more studies need to be undertaken, and judging from the SCCS’s comments, quality studies need to be undertaken.
Meantime, I can only conclude with this:
You should always choose and use what is right for you.
You: Would you use it, Lise?
Me: I prefer not to.
More about Aluminium, Allergies, and Antiperspirants
Antiperspirant and deodorant allergy test results:
"The most commonly occurring allergen in 107 tested deodorants and antiperspirants was fragrance - perfume." (LINK)
Agency for Toxic Substances and Disease Registry on Aluminium:
"An average American adult consumes about 7-9 mg of aluminium every day through their food." (LINK)
Human health risk assessment for aluminium, aluminium oxide and aluminium hydroxide (LINK)
Scientific Committee on Consumer Safety SCCS : The SCCS opinion on the safety of aluminium in cosmetic products (2014) (LINK)
A preliminary study og the dermal absorption of aluminium from antiperspirants using aluminium-26 (LINK)
Aluminium zirconium tetrachlorohydrate gly (another aluminium compound used in antiperspirants and allowed by the FDA at up to 20% of a formulation) (REF)
Frequent use of underarm cosmetic products (containing aluminium) may lead to an accumulation of aluminium in breast tissue (LINK)
FDA Code of Federal Regulations for Aluminium Chlorohydrate (LINK)
The book below (available in both Spanish and English) shows you how to make your own all natural preservative free deodorants with a shelf life of up to 6 months.
