UV filters are the most important active substances in suncare products – protecting users against the harmful impacts of UV radiation such as sunburn and skin cancer. However, there is growing concern that these substances could have potentially harmful effects on the environment. This has resulted in increased scrutiny and widespread public attention, in particular in relation to the possible impact of UV filters on coral systems. There is abundant human safety data and environmental compatibility studies available already, but much of this is only accessible to those with deep expert knowledge, leaving many consumers who want to make the best choices for themselves and the environment underinformed.

To help consumers and developers make informed decisions on UV filters and suncare products, and to show that it is possible to achieve environmentally friendly and more sustainable sunscreens, DSM has created a self-explanatory environmental impact scoring system, which allows online to generate an eco-score and a corresponding visual ecometer-label. 

Fig. 1 | The seven logos to visualize the relative environmental compatibility of UV filter combinations in sunscreens.

Here we will introduce the rationale and methodology that led to the creation of this eco-scoring system, and explain how it can be accessed now as part of the DSM Sunscreen Optimizer™ 2.0 with Eco profiling to help developers make informed choices for their products.  

UV filters under the spotlight 

UV filters require regulatory approval for use in sun protection products. Although legal requirements and authorities’ expectations differ across regions, many regulatory agencies have human efficacy and safety requirements in addition to rising environmental safety requests to be met.

Despite these environmental safety requirements, it remains challenging for developers to navigate a path to eco-compatible suncare products. In some instances, there is conflicting evidence around the impact of UV filters, causing confusion in identifying suitable compounds to use. From a consumer perspective, it can be difficult to understand where to find fast and suitable information and what data to follow. There is a danger of misunderstanding and consumers could refrain from using suncare products and thus expose themselves to an even higher risk of sunburn or even skin cancer. 

It was clear to DSM that there is an inherent need for a comprehensive system that allows end-consumers and manufacturers to easily discern the ecological impact and effectiveness of UV filter compounds and suncare products. This led us to develop our easy-to-understand relative eco-scores and eco-labels. Our approach was designed both to help developers to make environmentally sustainable products and to support consumers as they strive to choose products with low environmental impact.

Methodology

Our computer-aided approach offers a unique and independent eco-scoring system. It was created and is kept up to date by analyzing public product databases using a smart algorithm to derive sunscreen eco-scores and incorporating available knowledge and data on the eco-compatibility features of UV filters in a transparent and logical manner. 

As part of a straightforward, three-step process, UV filters are first analyzed based on standardized eco-toxicological data to generate an individual environmental impact (EI) score. Users can then rate the overall impact of a sunscreen composed of multiple UV filters by accounting for the concentration and impact of each respective UV filter. This overall eco-score can then be translated into an eco-label by ranking the environmental sustainability relative to other marketed products with the same SPF labelled. 

The scoring parameters used to calculate the EI scores were carefully selected to ensure that they comply with guidelines such as those of the ECHA (European Chemical Agency). The compounds are evaluated by their persistence and biodegradability (P), bioaccumulation (B) and determined toxic effects (T) for aquatic species, using values derived from mainly Organisation for Economic Co-operation and Development (OECD) guidelines within the ECHA dossier to ensure data standardization. Currently, each UV filter is given a score out of 100 based on the above-mentioned parameters. Toxicity is the highest weighted of the parameters due to its significant impact on the ecological effects of a UV filter. 

Please refer to the full publication for details on how each parameter is calculated or download the paper below.

Calculating eco-impact score for a single UV filter

To calculate the individual EI score for a UV filter, the points assigned to each of the above parameters are totalled and then this sum is subtracted from the maximum potential value of 100. The resulting score gives an indication of the environmental impact, with the lowest scores denoting the best environmental sustainability. 

Calculating eco-impact score for a suncare product with multiple UV filters

The eco-impact-scores for suncare products which include multiple UV filters are calculated based on the sum of the individual impact scores for each component UV filter multiplied by the percentage concentration of that filter. 

Assignment of eco-label

To convert this UV-Filter composition EI score into an easy-to-understand eco-label, it is necessary to compare it relative to other marketed products with the same SPF label – as sunscreens with higher SPF normally contain more UV filters. We used eight SPF classes, based on those defined in the EU (6, 10, 15, 20, 25, 30, 50, 50+), and generated for each a standardized distribution of product EI scores. The medians of these distributions are used to set the comparison points to assign our eco-labels.

Our eco-label classification system ranges from A−G, with A being the best and G the weakest. The mid-point of the seven-class system (D) is aligned to the median resulting from the SPF category-specific analysis.

Application and use

The user-friendly system described above is designed to support developers in achieving eco-friendly sun protection products (Fig. 1). It can help to design, or simply rate and compare sunscreen products, using a virtual eco-benchmark based on hundreds of marketed sunscreens. To create an eco-label, the user just needs to enter the quantitative composition of their suncare product (box marked in orange), while the three-step scoring system is automatically performed by the system. 

Fig. 2 | The DSM approach to eco-friendly sun protection.

Step 1: Evaluate environmental impact of individual compounds (UV filters at present, with the potential to extend to other ingredients). Step 2: Assess the combined impact that a selected UV-Filter combination would have on the environment when used in a sunscreen. Step 3: Benchmark the eco-impact score of the composition against the virtual market average to generate an eco-label and corresponding logo.

The tool will output a clear eco-classification that gives developers a relative score to indicate the ecological and environmental compatibility of their UV filter or product, as well as generating a simple eco-label that can be used on their products to support, guide and inform consumers of the ecological impacts of the product

With the novel eco-tool integrated into DSM’s Sunscreen Optimizer™, the extended platform serves now the environmental aspect in addition to the important efficacy estimations like SPF and UV-A protection performance for UV filter combinations. By providing this tool online and for free, we hope to create an environment where it is discernibly easier to create effective and environmentally conscious sunscreens.