Ingredients in sunscreens: Which ones are problematic?

The discussion about the harmfulness

Sunscreen products and their ingredients are frequently the subject of discussion due to their potential harmfulness, for a variety of reasons. This concerns the effects on both humans and the environment. Whether the filters used harm coral reefs or other marine life is a relevant question. There is also much speculation about which ingredients might be harmful to the human body itself. Understandably, this is confusing for consumers. On the one hand, it's said that sunscreens are necessary to protect against solar radiation, but on the other hand, it's unclear which sunscreens are actually effective or whether they might harm the user or the environment. Here, we will break down the most important aspects of this complex topic and provide you with an overview.

Chemical vs. mineral UV filters

First, it's important to distinguish between the different types of UV filters. Fortunately, there are only two. One type is chemical filters, also known as organic filters. The other is mineral filters, which are similarly referred to as physical or inorganic filters. For now, we'll simply use the terms chemical and mineral.

The way these two types of filters work is actually quite simple. Chemical filters absorb the energy of UV rays and convert it into heat. Mineral filters transmit the light rays by scattering and reflecting them. You can imagine it as if you have lots of tiny miniature mirrors on your skin when using sunscreen with mineral filters.

Both types of filters offer proven protection. Some creams even combine both types to create versatile protection. Whether you prefer chemical or mineral filters, or use one of the combination products, is entirely up to you and a matter of personal preference. There are advantages and disadvantages to both filter types. You can learn more about the specific uses of each filter and the validity of the concerns raised about them in the next section.

Harmfulness of UV filters

Among mineral filters, oxides are particularly questioned due to their effects on humans. In other contexts, they are considered potentially harmful and are therefore already banned in other types of personal care products. They are currently permitted in sunscreens. However, it is not yet fully understood whether the method of application makes a difference to the potential risks posed by oxides. Those who distrust oxides or want to play it safe should ideally avoid these filters.

But chemical filters are definitely not without their critics. Unlike mineral filters, they pose a greater risk to the environment. Some chemical UV filters are indeed harmful to the environment. If they enter the ocean, they can harm marine life, including algae and plankton. Certain chemical filters can cause coral bleaching. The filters can also end up in potential food fish or affect birds. To avoid this cycle, they should not enter seawater.

Among chemical filters, octocrylene is particularly criticized. Over time, it can decompose into benzophenone, a substance suspected of being carcinogenic. While these suspicions, like those of oxides, are primarily based on assumptions, avoiding octocrylene for safety reasons can be a sensible precaution.

Just because some filters, both mineral and chemical, are viewed critically and it's uncertain whether they can cause harm, doesn't mean that all filters have a bad reputation and should be avoided. Quite the contrary: there are many filters that can be used without hesitation, and sun protection is essential to protect your skin from damage. You simply need to consider which filters it should contain before buying sunscreen and carefully examine the ingredients of each product.

Unfortunately, the only way to decide which filters you don't want in your sunscreen is to do thorough research. The silver lining: there are also a large number of completely harmless chemical filters. At colibri skincare, we strive to create good products for people that are also environmentally friendly. Therefore, we deliberately avoid all UV filters that could be harmful. All our filters are harmless to both humans and marine life. They are certified coral-friendly and safe for all other marine life.

Nanoparticles in sunscreens

The use of nanoparticles in sunscreens is also viewed critically. However, here too, the data situation is not entirely clear.

First of all: What exactly are nanoparticles and what are they used for? Nanoparticles are extremely small particles, usually made of zinc oxide or titanium dioxide, which are used as mineral UV filters. Larger particles of these substances were previously used in sunscreens. It is now known that the size of the particles is responsible for the typical, undesirable white film that sunscreens leave on the skin. To offer more pleasant textures, many manufacturers have therefore switched to nanoparticles of the same substances.

That in itself doesn't sound particularly concerning. Unfortunately, the problem arises that nanoparticles might be small enough to penetrate the skin barrier. These are currently only assumptions and not established facts. However, it would be potentially extremely unhealthy if zinc oxide or titanium dioxide were to enter the human body. Avoiding nanoparticles as a precaution is a valid measure as long as their harmfulness is not fully understood.

If you want to use a sunscreen with nanoparticles, a lower dosage is definitely safer. This doesn't mean you should apply less product; it simply means you should use it on fewer days per week or only on specific areas of the body (e.g., only the face and neck, and the rest of the body with a sunscreen containing chemical filters). Finally, there's nothing wrong with using several different products, as long as you don't mix them directly together.

Incidentally, even the use of natural cosmetics is no guarantee that the products are free of nanoparticles, as these are sometimes used even by natural cosmetic brands. Unfortunately, here too, there is no alternative but to carefully check the list of ingredients and do your own research.

What should you pay attention to when buying?

With everything that one should potentially avoid, the question arises: how does one choose a good product that suits one's needs?

Our first tip is to avoid anything suspected of being harmful. As they say, better safe than sorry. So, opt for ingredients that are definitely safe rather than using something that you might find harmful in a few years based on new research. This leads us directly to our next tip: pay attention to seals of approval. There are certain certificates and seals that designate products as safe. These include, for example, the coral-friendliness seal. You can also always request information from the manufacturer. With so many controversial ingredients, it pays to be a critical consumer. The manufacturer should always be able to explain what is in their cream and why. And last but not least, you can make sure that there are also enough natural ingredients. Natural oils or active ingredients like shea butter or various vitamins are a good indication that you are applying substances to the sunscreen that your skin tolerates well.

How to handle expired creams

With skincare products, and especially sunscreens, you should always adhere to the expiration date and the stated usage period. This is because harmless ingredients can react over time to form other, potentially dangerous compounds. This applies to various chemical filters. Fortunately, none of the filters used in our Daily SPF 50+ Moisturizer react further. Nevertheless, we recommend using the product within its expiration date.

You can always find the expiration date on the symbol of the small cosmetic jar. For example, if it shows a six, this means that the product can be used safely for six months after opening. To avoid exceeding this period, it helps to write the date of first use on the packaging with a waterproof pen or attach a sticky note to the product. Products that have passed their expiration date should be disposed of.

Is there such a thing as natural sun protection?

The answer to this question is a qualified yes. As we explain in our articles " Summer, Sun, Sunscreen! " and "UV Radiation and its Effects on the Skin," the skin has a natural protection time. However, this is often only a few minutes. Many plant oils do have their own sun protection factor (SPF), but it is very low, usually in the single digits. Since you should apply at least SPF 30, the protection factor of plant oils is insufficient. Under no circumstances should you mix a sunscreen with plant oils or other skincare products to make it appear more natural. Sunscreens are formulated to guarantee the stated SPF with their exact composition of active ingredients and in sufficient quantity. Mixing a sunscreen with another product dilutes it. Just like using too little sunscreen, this reduces the actual level of protection and therefore its effectiveness.

Some filters are proven to be harmful to the environment, and others may also be harmful to humans. Expired creams should definitely not be used. However, using sunscreen to protect yourself from UV radiation is absolutely essential. Ultimately, it comes down to carefully checking the ingredients and, if in doubt, contacting the manufacturer to ask about the exact composition and safety certifications.