Nanoparticles in cosmetics - are they dangerous?

What are nanoparticles?

Nanoparticles are particles that are in the range of 1-100 nanometers (nm), thus at 1 × 10-9 that is 0, 000 000 001 meters, this is one tenth of the diameter of a human hair. The name "nano" is derived from the Greek "nanos" and means something like "dwarf" or "dwarfish".

What are nanoparticles chemically or physically?

Nanoparticles may consist of different materials, and may of course be e.g. produced by volcanic eruptions in the form of ashes or synthetically in the laboratory [2]. They are divided into several groups:

• Carbon containing e.g. Fullerene or carbon nanotube

• Metals e.g. colloidal silver (Ag) or gold (Au)

• Metal oxides e.g. Titanium white (TiO2) or zinc oxide (ZnO)

• Semiconductors e.g. Cadmium telluride (CdTe) or silicon (Si)

• Polymers e.g. Dendrimers^[3]

The big difference to the properties is their mass-to-volume distribution due to their small size. They obtain completely different properties, since other forces act on them, e.g. Quantum chemical principles and the fact that mass forces are not so strong, but surface forces are stronger. The large surface gives them higher chemical reactivity, better electrical conductivity, and greater surface charge, which requires compensation. Due to this required balance, the durability of nanoparticles is very short, as they quickly reassemble into larger clusters^[4].

How are nanoparticles made?

Nanoparticles are produced through complicated chemical or physical routes. For example, via chemical solutions or painting processes^[5].

What are their applications?

In addition to the technical applications, it is used in medicine as a drug carrier for targeted treatment of e.g. Cancer cells application, and is used in cosmetics in sunscreens, toothpastes and antiperspirants. In addition, they are used in the food industry as a thickener and anti-lumping protection^[6].

What do nanoparticles in cosmetics do?

Nanoparticles allow a wide range of applications, due to their variety of properties. For example, titanium dioxide and zinc oxide are used in sunscreens by spreading a clear film over the skin that reflects solar radiation. Nanoparticles Active ingredients quickly penetrate the skin faster than the larger particles could. And colloidal silver has an antibacterial effect, protecting it from unpleasant odors. Nanoparticles offer great properties in many ways to replace some of the worse alternatives and eliminate problems^[7].

Why nanoparticles as a substitute for chemistry in cosmetics?

In cosmetics, nanoparticles serve as a substitute for chemistry. They are most commonly used in sunscreens, in which chemicals such as Enzacamen are replaced. Enzacarmen has been shown to be involved in the growth of cancer cells, but apart from titanium and zinc nanoparticles, there are no alternatives. Enzacamen absorbs a part of the sun's ultraviolet radiation, which becomes harmless to humans through the so-called Stokes shift, when it will give off again^[8].

Are nanoparticles harmful?

This question has not yet been clearly proved or disproved, there simply are not enough studies and evidence for or against it. Titanium dioxide e.g. It is almost completely inert chemically, so it does not cause any damage even if it gets into the body. However, studies have shown that TiO2 is toxic in a way that is not yet detectable [9]. However, since there are no precise data for or against it, nanoparticles are to be enjoyed moderately, and to question their meaning as an ingredient. For example, titanium dioxide and zinc oxide may be harmful, but their property is more valuable than unproven toxicity to protect them from the sun's rays and skin cancer [10].

Sources:

Wikipedia^[1][3]

Article on possible health effects of nanoparticles^[8]

Report on the Benefits of Nanomaterials^[2][4][7][6]

Article on the production of nanomaterials by nucleation^[5]

Article on the effects of nanoparticles on aquatic organisms^[9]

FDA's opinion on Enzacamene^[8]

Image sources: Wikimedia Commons, Flickr. All image rights go to the owners of the images.