Accused of being bad for marine fauna and flora, and sometimes even for humans, sunscreens have been singled out in recent years. They are not simple cosmetics since they are a public health issue, the protection of the skin against the sun's rays. Can they be clean? Can we do without them?
Environmentalists and ocean lovers condemn sunscreens, dermatologists on the contrary recommend applying protective screens all year round while some influencers encourage not to use them at all to protect the planet . And 92% of French people want sunscreens to be more environmentally friendly.
Between chemical filters accused of being endocrine disruptors and, for some, of destroying coral reefs, and the problem of nanoparticles in mineral screens, the subject is thorny.
Let's just say it right away, the clean sun product has not yet seen the light of day. Because it is an eminently complex product to formulate, which responds both to a health problem and to a need to provide pleasure for good compliance, that is to say regular use. Moreover, if it is considered in Europe as a cosmetic - but with very strict regulations -, it is a "quasi-drug" in Japan and an OTC (Over the counter/medication sold without a prescription) in the United States and Canada, in the same way as paracetamol for example.
Filters in the dock
Sunscreens are suspected of polluting waters and killing corals, but also of being endocrine disruptors .
Some chemical filters banned for their environmental impact
Chemical filters absorb UV energy and cover the entire solar spectrum: UVB, UVA, long UVA and blue light. If they filter UV on the skin, they also do so in the water. Thus, the thousands of tons of non-biodegradable sunscreens dumped annually into bathing waters prevent the sun's rays from reaching the seabed and disrupt the organisms that live there.
- Chemical filters prohibited in tourist areas:
The Palau archipelago was the first, in 2020, to ban ten components including oxybenzone (Benzophenone-3 on the INCI list) and octinoxate (ethylhexyl methoxycinnamate), two chemical filters also banned in Hawaii since January 1, 2021. Territories with coral reefs, such as the US Virgin Islands or the Republic of the Marshall Islands, have also banned octocrylene. Sometimes, the use of any sunscreen is prohibited, particularly when visiting certain chasms and caves in Mexico or Lifou in New Caledonia.
Indeed, many studies have shown that these filters have a negative impact on marine organisms. To name a few: in December 2018, a study by French researchers revealed that octocrylene accumulates in corals in the form of fatty acid derivatives and can interfere with their metabolism. A new French study from March 2021 demonstrates that octocrylene is transformed into benzophenone by a chemical reaction as soon as it is produced, and that its concentration systematically increases over time in finished products. In addition, a study published in 2015 by researchers at Tel Aviv University revealed that oxybenzone – or benzophenone – distorts the morphology of coral larvae by damaging their DNA.
- A ban to be put into perspective
The experimental conditions of these studies are most often very far removed from what happens in reality, because exposure to chemicals is generally extreme – short and intense at the same time – and does not reproduce the conditions in a natural coral environment. The reference method for testing the effects of sunscreens is to take small samples of coral, bring them to the laboratory, and expose them to varying concentrations of sunscreen (or their components). The amount of algae released, the color of the corals, the number of survivors, etc. are then measured.
In fact, it is not so much the amount of sunscreen applied when swimming that is harmful, but the overall sum of filters that end up in the water, coming from multiple uses of these substances (in food, construction, etc.). Thus, the concentrations of benzophenone found in samples taken from swimming areas on beaches in California are much lower than those measured in sediments taken near sewer outlets - where no one swims - and those used to detect their negative impacts in the laboratory. So, if sunscreens play a role in the discoloration of coral in the wild, it is a minor action compared to the massive impacts of warming of water masses, their acidification, discharges of poorly treated wastewater, plastic pollution and carbon emissions.
What about endocrine disruptors?
The other major accusation that weighs on chemical filters is that of endocrine disruption. We repeat, nothing is proven, because it is very difficult to demonstrate. However, the following are suspected among chemical filters: avobenzone, ethylhexyl methoxycinnamate (octinoxate), benzophenone-1 and -3 (oxybenzone), octocrylene, 4-methylbenzylidene camphor (4-MBC) and homosalate. According to the standards set by European regulations, the quantities applied, limited to a few months per year, are not problematic. But discharged into water, unfiltered by treatment plants, they are ingested by living organisms that end up on our plates.
Mineral screens, really harmless?
European regulations authorize two mineral sunscreens: Titanium Dioxide and Zinc Oxide. They are called mineral screens because they act as sun visors, forming like small mirrors stuck to each other on the surface of the skin that reflect light. Organic sunscreen brands claim that they are safe for humans and the environment and therefore a healthy alternative to chemical filters. And yet…
- Not so good for the environment

Tests have shown that exposure to zinc oxide disrupts the photosynthesis of algae that live in coral tissue, causing them to discolor. Some conventional and certified organic brands have therefore excluded it from their products. In addition, zinc oxide and titanium dioxide are not biodegradable and tend to accumulate in aquatic environments.
Another concern is that mineral screens all contain a significant amount of these two substances in the form of nanoparticles – extremely fine particles – which can penetrate biological barriers. A study from Wageningen University in the Netherlands observed that these microscopic elements disrupt the feeding behavior and reproduction of mussels. They are also known to modify the genetic code of certain fish, preventing their reproduction. Other studies suggest that nanoparticles could be toxic to plankton.
- A risk for humans?
Titanium dioxide (nano-particulate or not) has been classified as a possible carcinogen by the WHO since 2006, in case of inhalation at high doses. This is why it must be handled with care by formulators and manufacturing personnel.
Another concern: mineral-based sunscreens have often been criticized for being thick and white. And yet, it is not because they appear to provide more coverage that these products protect better. Indeed, while conventional sunscreens combine between 3 and 7 filters to obtain a filtering system that covers the entire solar spectrum (UVB, UVA, blue light), in organic products, only zinc oxide and titanium dioxide are authorized. It is therefore difficult – especially if they are not used in nano form – to obtain uniform and highly effective protection, particularly on long UVA rays (which penetrate deeper into the skin). In this non-nano form, i.e. larger, they do not completely cover the skin, because they tend to create "clusters". And in
Finally, the mention
Formulas in great evolution
Aware of the ecological and human impact of their formulas, solar specialists have initiated research work to improve their products .
Optimize filter content
For the past ten years, the leaders in solar have been reviewing their formulas. As studies and discoveries progress, they have avoided certain criticized filters. They have also improved the synergies between filters in order to reduce their number, but also their concentration in sunscreens. Where there were – and still are in some – seven associated filters, some brands have managed to use only three to four for the same protective effectiveness. And to reduce the concentration in the overall formula to less than 20%.
These same laboratories try to use only filters that are not soluble in water, so that they do not spread into the oceans.
Improve the overall formula
As we have just seen, filters only represent 20 to 30% of a formula. It is therefore important to look at what is around them: silicones, mineral oils, ethoxylated molecules (ending in eth), alcohol, parabens. Here again, more and more manufacturers are removing ingredients that are harmful to the environment, either because they are of petrochemical origin and bioaccumulative (mineral oils, silicones), or because they disrupt ecosystems such as volatile silicones (cyclypentasiloxane, cyclohexasiloxane, BHT).
At the same time, they create finished products that are as waterproof as possible, so that they spread as little as possible in the water.
Improving biodegradability

One way or another, sunscreen ends up in the oceans. For example, 25% of sunscreen is released into the water after 20 minutes of swimming. And since there is always some left on the skin in the evening, the rest goes there indirectly after showering via wastewater. Each year, tourism generates the discharge of nearly 25,000 tons of sunscreen into the waters of tropical countries, including 4,000 tons in coral areas.
This is why manufacturers have also revised their copy concerning the biodegradability of their products, to the point of displaying biodegradability rates above 90%.
Finally, "non-ecotoxicity" is now tested in the laboratory on algae, corals and plankton by oceanic study centers: the Banyuls-sur-Mer Oceanological Observatory, the Mediterranean Institute of Biodiversity and Ecology, the Scientific Center of Monaco.
Packs with less plastic
Beyond the formulas, we know that the other concern with sunscreen products is the tons of plastic bottles that invade the beaches and end up in the oceans. Even if it is primarily water or soda bottles that pollute the most beautiful places on the planet, the cosmetics industry is aware of its necessary participation in the collective effort by reducing its consumption of virgin plastic (newly produced plastic).
This is why many large groups now offer bottles made from recyclable and partially or 100% recycled plastic . When you have finished your cream container, you throw it in the recycling bin (in countries where recycling is effective). The start-up Carbios is innovating with PET bottles that are infinitely recyclable thanks to an enzymatic process. As for tubes, we have seen the first partially recyclable tube made from cardboard, thus reducing its weight in plastic by 45%. So everything is not perfect yet, but we are making progress.
Solar energy, a public health issue
Even if they are not flawless, sunscreens are not cosmetics like the others. They meet a public health need.
The sun, a health hazard





More than 100,000 new cases of skin cancer are recorded each year in France, including 15,500 melanomas (Overview of cancers in France 2021). According to the WHO, the incidence of melanoma and other skin cancers has increased in recent decades (with an incidence rate doubling every 10 years in countries with a Caucasian population). Currently, between 2 and 3 million non-melanoma skin cancers and 132,000 malignant melanomas are recorded each year worldwide. One in three cancers diagnosed is skin cancer according to the Skin Cancer Foundation Statistics. The sun and its ultraviolet rays are the main culprits.
But the sun has other visible harmful effects on the skin, much more widespread: sunburn, sun allergies, actinic keratoses, spots, photo-aging.
The best protection: clothing and shade

Obviously, the best sun protection remains a T-shirt or loose clothing, a hat, sunglasses and staying in the shade. In case of exposure, it should be as short as possible, during the coolest hours. But there are still walks, hikes, sports or gardening sessions where certain exposed parts of the body must be protected (nose, ears, neck, décolleté, hands, ankles).
Essential sun protection

Sun protection is therefore non-negotiable during exposure. And by exposure, we mean any outdoor activity between May and September. It is better to apply a sunscreen product 4 months a year than risk burning, allergies, spots, actinic keratosis (red and rough lesion linked to overexposure, one of the leading causes of consultation with dermatologists) or cancer. So, we choose a sunscreen that is in line with our beliefs, our tastes in terms of galenic (oil, spray, milk) and we adopt responsible behavior by exposing ourselves little and wearing sunglasses, a t-shirt or a dress. This is what we call the benefit/risk.
Regulations that reduce opportunities for development
There are few brands that manufacture sunscreen products compared to those that manufacture makeup or skincare. And over the years, we even see laboratories abandoning this segment. This shows how difficult it is to correctly and effectively formulate these products that do not tolerate ease. As for making your own sunscreen product at home, out of the question!
A positive list of filters in the various regulations
Since sunscreen products are subject to a much more stringent performance requirement than a moisturizer or shampoo, they are governed by much stricter regulations. One of these is the positive list of authorized UV filters.
Sunscreen products belong to the family of cosmetic products, and are subject to European Regulation EC No. 1223/2009. Annex VI of this regulation currently authorizes around thirty filters, evaluated by the European Scientific Committee for Consumer Safety, and indicates their maximum permitted concentration. Laboratories must imperatively draw from this positive list to formulate any care claiming a protective action against UV rays.
The difficulty in registering new filters
In order to improve the quality of filters and develop sun protection, many laboratories are working on new protection processes, filters or others. But they are coming up against several major obstacles:
- The complication of finding new effective molecules, especially when we are looking for naturalness with ingredients derived from plants and no longer from petrochemicals.
- Time, because it takes several years to test its effectiveness, safety and non-toxicity.
- Once these steps have been completed, there remains the regulatory barrier, the slowness and sometimes the administrative protectionism to overcome. The Pierre Fabre group, which has just put a new filter on the market in 2021, took almost ten years to have it registered in the European list. As for the FDA, the American body is only just beginning to look at its list of authorized filters dating from 1974, well before the harmful effects of UVA were discovered or the environment was concerned! Not to mention the reluctance of this organization towards filters from non-American laboratories!
In such a context, we understand the difficulty in innovating in the field of sun protection and especially why certain laboratories, followers of "clean" are giving up, dissatisfied with the answers they could provide immediately.
Although truly clean sun care still does not exist, great strides have been made in terms of protective effectiveness and eco-responsibility.
What progress between the products of the early 2000s and those of today - and what about the bottles of Monoï without protection from the 70s! -. We can therefore hope, in a few years, for a design of cleaner, more ecological and healthier formulas, reconciled with filters (if they still exist).