It is startling news: In recent weeks, authorities have increasingly detected a metabolic breakdown product of plasticizers in urine samples from hundreds of daycare children and adults. Its name: Mono-n-hexyl phthalate. First the State Office for Nature, Environment and Consumer Protection of North Rhine-Westphalia found what they were looking for, then the Federal Environment Agency during the preliminary data evaluation of the German Environmental Study.
The critical thing about it is that the substance is considered to be harmful to reproduction and health. But where does he come from? Why is it suddenly occurring more frequently? The search for causes is ongoing. There is no clarity yet – only speculation. Sunscreens are mentioned as a possible source, also because the urine samples from the summer months were noticeably increased – what’s the truth? We have compiled the current state of knowledge.
All questions at a glance Plasticizers and UV filters under discussion What still applies to sun protection
Plasticizers and UV filters in discussion
What substance was detected in the urine samples?
It has the complicated name mono-n-hexyl phthalate, MnHexP for short. It can arise as a metabolic breakdown product of various plasticizers in the body. Scientists are currently investigating whether it is formed from the plasticizer di-n-hexyl phthalate (DnHexP).
Are the suspected plasticizers allowed in cosmetics?
The deliberate use of DnHexP in cosmetic products is prohibited according to the EU Cosmetics Regulation. Other starting materials that could lead to the appearance of the degradation product MnHexP are currently being examined as possible sources.
Research into the causes is going in different directions: plasticizers can migrate from certain plastic packaging into cosmetics and food. However, products can also be unintentionally contaminated during the manufacturing process – a frequently used UV filter has come into discussion.
Could a sunscreen filter be the source of the exposure?
This is currently completely open. The UV filter Diethylamino Hydroxybenzoyl Hexyl Benzoate, or DHHB for short, is suspected. Apparently the plasticizer DnHexP is formed as a by-product during its production, which in turn could be metabolized by the human body to form MnHExP.
The Federal Institute for Risk Assessment (BfR) points out that, in addition to sunscreens, other products could also be considered sources. To date, the BfR has “no reliable information that cosmetic products containing UV filters are actually contaminated to a relevant extent with substances that could lead to the formation of MnHexP”.
How dangerous to health are the pollutants found in urine so far?
The Federal Institute for Risk Assessment writes in a statement that both the intake of the degradation product MnHexP and its possible starting materials “should be reduced as much as possible”.
According to initial, preliminary model calculations, the concentrations detected in the urine samples “do not give rise to increased concern.” According to the current state of knowledge, sunscreens that are contaminated with DnHexP do not pose an acute danger and health impairments are “very unlikely”. The fact that MnHexP can be detected in the urine does not pose an immediate health risk.
Has Stiftung Warentest already detected plasticizers in sunscreen?
No. So far we have not tested sunscreens for plasticizers. In the next test we will address the current issue.
However, our tests show that sunscreens generally contain significantly lower amounts of the UV filter DHHB than the EU cosmetics regulation allows. This allows up to 10 percent. In our test tables we always state the UV filters included transparently, including sunscreens for adults – every second one has DHHB as an ingredient. It is listed in the table under “Type of sun protection filter” with the letter “j”.
What still applies to sun protection
Should I avoid sunscreen now?
No! It remains essential to comprehensively protect the skin from damaging UV radiation. None of the suspicions that have arisen so far justify waiver. However, it is clearly proven that UV light can cause sunburn and, in the long term, even skin cancer. Regular, generous application of cream, tightly woven clothing and extensive breaks in the shade provide protection.
Can I continue to use sunscreen with the DHHB UV filter?
Yes. The Federal Institute for Risk Assessment considers any health impairment to be unlikely. This would also apply if sunscreens contained up to 10 percent of a UV filter contaminated with up to 0.3 percent DnHexP – a generous assumption.
The Karlsruhe Chemical and Veterinary Investigation Office has also already reacted and is currently testing sunscreens for DnHexP. The experts found what they were looking for in some of the products. However, the detected levels are consistently below those in the model calculation of the Federal Institute for Risk Assessment, so that they should not pose any health impairment.
Tipp: Stiftung Warentest regularly deals with topics related to skin cancer prevention and treatment, for example when testing skin screening apps and evaluating medications for actinic keratosis, a precursor to non-melanoma skin cancer.
How should I protect myself and my child from the sun?
Sun creams, lotions and sprays are important aids – including those with the UV filter DHHB. If you want to avoid it as a precaution, you can also find products in our database that do not contain DHHB: In our test of 19 sunscreens for children in 2023, there were seven that did not use the filter – but not all of them delivered the promised sun protection. In the test of sunscreen for adults, ten got by without it.
Tipp: In our test tables we indicate the UV filters included; in the line for the sun protection filters, pay attention to the letter “j”, which stands for DHHB.