A-Closer-Look-At: Sunscreens (part I)

Sunscreens – part one: How do sunscreens work?

The big question is of course, why should you use sunscreen. Sunscreen is good for preventing sunburn. The red color of sunburned skin is a tell-tale sign that skin cells are damaged. Damage can be induced by UVA (Ultra violet sub type A) and UVB (Ultra Violet sub type B). There is also UVC (Ultra Violet sub type C), but the ozone layer prevents UVC from entering the atmosphere. UVB increases melanin production in the skin, which makes us tan, and also causes sunburn.

UVA is perhaps even more dangerous. UVA is able to penetrate deeply into the skin, ages skin quickly and damages DNA. Damaged DNA can lead to cancer (okay, I have to admit, that the fact that ‘DNA damage causes cancer’ is a very, very brief summary about what causes cancer. Even now, scientists are still trying to figure out how and why cancer exists.)

UVA isn’t blocked by glass or the clouds. Unlike UVB, UVA doesn’t give you any warning signs. You’re not going to get a sunburn or a tan. UVA is present every day, in every season, whether it is overcast or not. My first advice would be  to wear sunscreen (with at least SPF 15) every day. My second advice is to wear a broad spectrum sunscreen which protects you for both UVB and UVA. You should be able to tell from the packaging if this is the case.l

Oh, and it is wise to avoid sunbeds, according to a study in 2007, even one visit to a sunbed can increase your chances of getting skincancer (melanoma, the most dangerous kind) by 19%! (International Agency for Research on Cancer Working Group on artificial ultraviolet (UV) light and skin cancer. The association of use of sunbeds with cutaneous malignant melanoma and other skin canacers: A systematic review. Int J Cancer. 2007: 120: 1116-1122.)

How do sunscreens work?
There are two types of sun filters; chemical and physical.
Chemical filters (oxybenzone, octyl methoxycinnamate, octocrylene and avobenzone) are absorbed into the skin and absorb UV radiation. A number of chemical filters can be absorbed by the body and end up in the bloodstream. Others can generate free radicals (free radicals are bad!) when they react with the suns rays and therefore cause skin damage. This also happens if you don’t use a sunscreen!

Physical sunfilters stay on the skin and reflect the light. Good examples are titanium oxide and zinc oxide. They create a barrier to protect the skin by not allowing harmful chemicals to enter the bloodstream. They are known to not cause irritation. A drawback is that physical sunscreens leave a white film on the skin. If these sunscreens don´t leave a white film, nanotechnology is used.

What is nanotechnology?
Nanotechnology is the use of very, very tiny particles to enhance the performance of a product. The name derives from a nanometer. A nanometer is one billionth of a metre. Nanotechnology is the study of manipulating material on a molecule or atom scale. It is a relatively new study, so long term health effects are not known yet. The main concern is whether or not the particles can be absorbed by the skin and other cells of the body. This could lead to a higher dosage of the chemical in your body. The dosage of a chemical is linked to its toxicity. How higher the dosage, the more dangerous (poisonous) a chemical is. The main concern is if nanotechnology can penetrate the skin and cells. If yes, it could be dangerous, if not, we don´t have to worry. Unfortunatley, this is still being researched, so I can´t give a clear statement whether or not nanotechnology is advisable or not.

What is SPF?
SPF, sun protection factor is a (laboratory) logaritmic measure of how effective a sunfilter is. This is mentioned on the bottle. The SPF is the amount of UV radiation required to cause sunburn on skin with the sunscreen on in comparisation of the amount UV radiation required without the sunscreen.

It is said that the number of SPF determines how long one can stay in the sun without re-applying the product. For instance, if you get a sunburn from one hour of exposure to the sun, you should be able to stay in the sun for 15 hours with an SPF 15 on. This is not true. The intensity of radiation varies considerably with time of day. In early morning and late afternoon, the radiation has to pass through more of the atmosphere because the sun is nearer the horizon. The amount of SPF is determined by factors like skin type, the amount of sunscreen that is applied and the frequency of re-application, activities (sports, swimming) and the amount of sunscreen the skin has absorbed.

It is therefore recommended to re-apply sunscreen (half a teaspoon every application for the face and a shotglass for the rest of the body) every two hours and to stay out of the sun during the hottest hours of the day (12.00 – 15.00) of the day. Or go and have a nice long lunch in the shade. Or take a siesta.I mean, it’s vacation anyway.

Make up has an odd number of SPF (for instance, SPF 8 or 18) because first, the product is formulated and then the SPF is measured. Usually, an SPF in make up, or in a sunscreen in spray form isn´t as effective as a  regular SPF because you have to apply the sunscreen thickly. With a spray, it is usually not easy to determine where, how thickly and evenly the sunscreen is applied. With make up it is the same way. To get the SPF that is indicated on a foundation or powder, you have to put on the foundation very thickly (a.k.a. cakey!). So it’s always better to use a sunscreen under your day cream and makeup.

SPF can’t be increased by layering it. I will explain this with an experiment. Take two glasses. Fill them with water. Add to each glass the same amount of food coloring (or dye), for instance, 3 drops. Mix well, and take half of the first glass. Put this in a new glass. Now take half of the other glass, and put it in the third glass as well. Has the color changed? No. So, if you use a daycream with SPF 15 and a foundation with SPF 15, you will not get SPF 30. It will only help you to reach the required half teaspoon of sunscreen.

As I said earlier, SPF is a logaritmic scale. This means that SPF stops 93% of the UV rays (UVA or B depending on the sunscreen). Factor 30 stops 97% of the radiation. A higher factor is not always better. The higher the SPF, the more greasy the product will feel like. If your skin type is average (meaning not extremely fair), I would recommend sticking with SPF 15 in the winter and SPF 30 in the summer.

A wee bit extra
Next to a good sunfilter, it is also wise to check the rest of the sunscreen. Are there irritating ingredients in the sunscreen, like perfume, PABA, coloring agents, methylisothiazolinone, tea tree oil, witch hazel, ylang ylang, mint or citrus? Alcohol is not good either, unless it is a fatty alcohol (just type in the name of the Alcohol in wikipedia, and scan the page on the word “fatty alcohol”. For instance, cetearyl alcohol is a fatty alcohol).

And last, but no means least, after tanning/staying in the sun and using a sunscreen, hydrate your skin! Take a luke warm shower or apply aloe vera to cool the skin. Or use after-sun.

In the next post about sunscreens, I will talk about different kinds of sunscreens, and which ones to look out for!

Until next time,
Dymphy

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Read-the-Label: FACE Atelier Lip Glaze

Today I wanted to do another lip product and I choose the Lip Glazes from Face Atelier.

FACE Atelier Lip Glazes are available in 10 beautiful and versatile colors: Clear, Ice, White Gold, Flamingo, Peach, Cameo, Dianthus, Primrose, Plum and Shiraz and come in generous tubes of 15 ml/.5 fl.oz. at € 21,50. An enduring industry staple!

 

 

What’s in the product?

Polybutene, Octyldodecanol, Petrolatum, Beeswax, Ozokerite, BHA, Trihydroxystearin, Ascorbyl Palmitate, Tocopheryl Acetate, Butyrospermum Parkii, Silica, Methylparaben, Propylparaben, Retinyl Palmitate, Squalene.

May Contain: Titanium Dioxide, Iron Oxides, Mica, Carmine, Red 7 Lake, Red 6 Lake, Red 30 Lake, Red 33      Lake, Red 27 Lake, Red 28 Lake, Red 36 Lake, Red 21 Lake, Yellow 5 Lake, Blue 1 Lake, Tin Oxide, Calcium Aluminium Borosilicate.

Polybutene is a polymer that is used for lubrication and thickening. It ensures that the application is even and smooth. Octyldodecanol is an alcohol, which is a surfactant. It is used as a thickener and emulsifier. It also gives the product a bit of opacity and provides lubrication. Petrolatum can form a film and is also used as a thickner. Beeswax is a thickening agent with some moisturizing capacities. It is made by bees, so this product isn’t vegan. Ozokerite is a mineral that is a thickening agent.

BHA, betà hydroxy acid, also known as salicylic acid (aspirin is acetylsalicylic acid, and thus closely related), is an exfoliant which is probably used in a concentration of 0,5 to 2%. BHA has the ability to penetrate into the pore, and therefore can exfoliate inside the pore as well as on the surface of the skin. Trihydroxystearin is a mixture of fatty acids and glycerin and is used as a moisturizer and thickening agent. Ascorbyl Palmitate is the stable form of Vitamin C, and acts as a anti-oxidant. Tocopheryl Acetate is also a vitamin and anti-oxidant, Vitamin E. Butyrospermum Parkii, also known as Shea Butter and should be listed as Vitellaria paradoxa, is a thick butter that is renowned for it’s moisturizing properties, but can be used as a thickener as well. Silica, a mineral is used as a thickener.

Methylparaben and Propylparaben are the preservatives which stop the formula from going rancid. They are the most safe and effective preservatives. Retinyl Palmitate is better known as Vitamin A, an anti-oxidant and Squalene is an oil which could be derived from sebum, plants (mostly olives) or shark liver. It’s a natural component of the skin, and thus can moisturize the skin. It also has antioxidant and immune stimulating properties.

Now onto the “may contain” list. Keep in mind that the ingredients in this section are added in such low quantities, that is has no other effect than to color the product. For instance, Titanium Dioxide has some thickening properties, but because of the low concentration, it only acts as a white pigment. Same for iron oxides, a group of chemical compounds with have range of colors such as yellow/orange/red/brown/black. Mica is white as well. Carmine (derived from bugs), Red 7 Lake, Red 6 Lake, Red 30 Lake, Red 33 Lake, Red 27 Lake, Red 28 Lake, Red 36 Lake, Red 21 Lake are pigments used for their red color, Yellow 5 Lake is yellow, Blue 1 Lake is blue, Tin Oxide can give the product, in stable form a blue-black color or in metastable (the stability is long, but not infinte) a red color. Calcium Aluminium Borosilicate is another preservative.

It is a bit weird is that a polymer is the major ingredient. No water or any kind of (cheap) oil is used as a carrier for the other ingredients, but then again, based on the ingredientlist, this is a quite a thick liquid, so I shouldn’t be surprised.

Until next time,

Dymphy

A-Closer-Look-At: Cetearyl Alcohol

Many people cringe when they see alcohol on an ingredientlist. And they should, because the alcohol/hydroxy group dries out the skin. The hydroxy group that makes alcohol an alcohol, consists of both an oxygen (symbol: O) and a hydrogen (H) atom. A hydroxy group can form a hydrogen “bridge” with another water molecule. It basically pulls out water and takes it with it when you, for instance, wash it off your face.

But why is cetearyl alcohol (or cetostearyl alcohol/cetylstearyl alcohol) good for the skin? That is because of it’s fatty acid tail. The tail usually has an even number of carbon atoms, ranging mostly from 8 to 22 carbon atoms, although 36 or more aren’t an exception.

To be more precise, Cetearyl Alcohol is a mixture of fatty alcohols, of which cetyl and stearyl alcohols make up most of this ingredient. Since cetearyl alcohol has a polar, (water loving) head and a non-polar (oil loving) head, it is a surfactant. It can therefore be used as an emulsifier, stabilizer, opacifying agent (cetearyl alcohol turns into a white, waxy solid at room temperature) and a foam boosting agent.

Cetearyl alcohol was first extracted from whale oil, but since commercial whaling is forbidden, cetearyl alcohol is now produced from vegetable oils, like palm or coconut oil. It is also an end-product of the petroleum industry. It can also be made synthetically, from, for instance, breaking up triglycerides (three fatty alcohols bound together). The source can determine the amount of carbon atoms. For instance, rapeseed produces longer molecules of about 20 tot 22 carbon atoms, whilst coconut oil will yield molecules with 12 to 14 carbon atoms.

Please be careful if you have sensitive skin, cetearyl alcohol can possibly worsten dermatitis.. If you don’t have dermatitis, cetearyl alcohol is a very safe to use moisturizer and surfactant.

Until next time,
Dymphy

A Closer Look At: Surfactants

Surfactants

The group of surfactants is large and are mostly overlooked by chemists. That’s somewhat strange because the cosmetic industry/chemistry almost revolves about surfactants. They are right, because surfactants can be found in a lot of producttypes. You can find surfactants in bodylotions, eyeshadows, toothpaste and much more. They can cleanse, act as an emulsifier, solublize, condition and they some have nice extra’s (like a pearly shine).

But why are surfactants so important? Although not beautyrelated, mayonaise is a good example. Ever tried making it? I did, and I failed (hey, this was like, in second grade in high school). Mayonaise is a bit tricky to make, because you have to make sure that the temperature and the ratio of the egg and the oil are correct. If not, good luck trying (I blame my failure on the temperature – if you ever try making mayonaise, make sure that the oil and the egg have the same temperature – my egg came straight out of the fridge).

Back to beautyproducts. The key to its importance is that it could mix up anything. As in, really anything. And the reason for that is it’s unique structure.

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