The pros and cons
We can barely conceive just how tiny they are but are they a big problem? Good investigates.
It’s likely the moisturiser, foundation or eyeliner that you are currently using contains nanoparticles. And, given these are such tiny things you have probably given them nano thought. Nanoparticles are nothing new, though their increased use and application by the cosmetics and skincare industry is, in some cases, causing alarm.
They’re everywhere, says Snowberry skin scientist Travis Badenhorst, though there is an unfair stigma associated with nanoparticles, much like parabens, in the skincare space today.
“It all comes down to what is the actual nanoparticle composed of. Water, for example, is 0.27 nanometres in diameter,” says Badenhorst. “Nanoparticles tend to get a bad name because of their surface-to-volume ratio, which increases reactivity, and allows them to pass
through cell membranes. I believe they are necessary, but like all chemicals and particles, you should research their safety on your own as most companies won’t do that for you!”
While nanoparticles can be found in cosmetic products such as foundation, many experts agree that they have no place in eyeshadow, moisturisers, foundations or powdered make-up, says Badenhorst. “Nanoparticles, almost certainly, do get absorbed to some extent by the skin. Remember that the defined size of a nanoparticle is between 1-100 nanometres,” says Badenhorst. “Therefore, the depth of penetration into the skin is highly dependent on the size and concentration of the substance or particle in question.”
Why cosmetic companies use nanoparticles
Nanoparticles can offer better UV protection, deeper skin penetration, long-lasting effects, increased colour and finish quality. Nanocosmecueticals provide controlled release of active substances. They are used in haircare preparations, such as in treatment for hair loss, and can make fragrances last longer.
Carbon black, an intense cosmetic colourant, can also be used in the nano form and is a good example of how reducing the pigment particle size can alter the strength and opacity of colour.
The use of nanoparticles, particularly in sunscreens, protects against skin cancer, says Badenhorst. “There have literally been hundreds of studies performed on zinc oxide and titanium dioxide nanoparticles and from the overall picture, the benefits of using nanoparticles in sunscreens far outweigh the alternative. Our bodies metabolise and need these trace minerals and so I wouldn’t give it a second thought in using them.”
Are nanoparticles safe?
“The world is still discovering the answers to this question,” says Badenhorst. “There certainly isn’t a blanket answer for this. We as consumers should take a pragmatic approach in our cosmetic choices.”
The long-term consequences of such nanoparticles absorption are unknown. It is important to consider each material on a case-by-case basis and not bunch all nano materials together as “potentially unsafe”.
“There is not enough information on the long-term effects of manmade nanoparticles on human health and the environment,” says Aleph Beauty founder Emma Peters. “The pure fact that these particles can access reaches (skin and environment) that they weren’t naturally intended to, makes me question the safety of using nanoparticles in our products.”
Of course, “nano” just refers to the size of the material, not the other properties of the material, and not all materials in the form of nano will have the same consequences on the human body and the environment, explains Peters. “Some may be far more detrimental than others, and the application of a product can be a factor as well. I’m sure there will be different consequences if an ingredient is ingested, inhaled or absorbed. From our perspective as a colour cosmetic company, we don’t see the need to use nanoparticles in our products, so we consciously avoid ingredients of that size.”
The new European Cosmetic Organic and Natural Standard (COSMOS) doesn’t allow ingredients containing nanomaterials, and all organic products certified by ECOCERT must meet some fundamental criteria, such as absence of nanoparticles. However, these certification bodies have assessed certain nanomaterials in cosmetic products as safe. For example, some nanomaterials, such as mineral derivatives (titanium dioxide or zinc oxide) are accepted in sunscreen products certified organic.
“So far studies seem to show no or very limited absorption of nano zinc and titanium in sunscreens when applied to the skin – the skin is a barrier after all. However, the risk increases if these tiny particles are inhaled so avoiding aerosols containing nano ingredients is important,” says Liz McNamara, natural health expert for HealthPost.
An 2018 Amity University study* concluded that “stringent laws should be imposed on the regulation and safety of cosmeceuticals and nanoparticles used in them”.
How do you know if a product contains nanoparticles?
In Europe a new way of labelling is being introduced so that if an ingredient name is followed by the word “nano” in brackets it means that this ingredient is classed as a nanomaterial. i.e. it fits the definition provided by the EU cosmetics law. For example, Silica Silylate (Nano).
In New Zealand, the use of nano must be specified on the label of a product, says McNamara. “Brands must also notify the Environmental Protection Agency (NZ) if they are importing or manufacturing a product containing nanoparticles other than zinc oxide or titanium dioxide,” she says.
However, according to Badenhorst most companies don’t even know they are using nanoparticles. “I would therefore be wary if companies claim nano-free. If they truly are, just ask for proof. Nanoparticles do make certain skin care formulations more effective and more commonly, are known to increase the efficacy of sunscreens by improving UV protection in them. So they are everywhere and it’s really hard to provide a no-go list.”