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Toddler with plastic toys: strict limits
Photo: Bradley Hebdon/Getty Images
An increase in the load by up to tenfold – within three years. What toxicologist Holger Koch measured shortly before Christmas was something he had never seen before. “And I’ve been carrying out these analyzes for 20 years,” says Koch on the phone.
Koch heads a laboratory at the Bochum Institute for Prevention and Occupational Medicine of the German Statutory Accident Insurance that is one of the leaders in detecting phthalates. These chemicals are used as plasticizers in numerous products, including shower curtains and baby products, cables, packaging and artificial leather and cosmetics.
Koch regularly examines random urine or blood samples for the substances. At the end of last year, he came across a substance called mono-n-hexyl phthalate, MnHexP for short, in more than half of a total of 250 urine samples from kindergarten children from 2020 and 2021. It is the breakdown product of a harmful phthalate. “Highly worrying,” he calls the result.
The discovery also alarmed the relevant authorities. The parent substance of MnHexP is considered particularly toxic because it can impair human fertility. The amount detected does not necessarily have this effect, but according to the authorities it can harm health.
A few days ago, the North Rhine-Westphalia State Office for Nature, Environment and Consumer Protection reported the increased levels in the urine of kindergarten children. The Federal Environment Agency came across similar findings in a preliminary evaluation of the German Environmental Health Study, which is still ongoing. All abnormal urine samples were analyzed in Koch's laboratory. He was amazed not only by the contamination, but also by the material itself: “It was the first time I had seen such high detection rates for this unauthorized plasticizer,” says Koch.
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How can it be that a breakdown product of a banned substance is found in large quantities in German urine samples?
Phthalates are added to materials to make them soft, pliable and stretchy. They are almost ubiquitous – and sometimes problematic. Some of these phthalates are so-called endocrine disruptors; they influence the human hormonal system. Studies have shown that endocrine disruptors reduce the production of the hormone testosterone in the body.
This is particularly critical during pregnancy because male fetuses rely on testosterone for their development in the first trimester of pregnancy. In studies with rats, male offspring were born with malformed sexual organs when their mothers lacked testosterone. Harmful effects on humans have also been proven.
In the European Union, the use of many phthalates has been severely restricted in recent years due to health risks. For some products, certain substances are completely banned, in other cases, such as food packaging, strict limits apply. “In our analyses, we observed a ten to twenty-fold reduction in exposure to the particularly critical phthalates,” says Koch, “a clear success of the regulation.”
Resourceful producers
The latest find does not fit into the picture of this success story.
It is not yet clear from which starting material the degradation product MnHexP comes. Experts believe the most likely cause is a plasticizer called di-n-hexyl phthalate. It is considered particularly harmful and is therefore not permitted in cosmetics, food contact materials and toys.
The raw material may also be a new type of phthalate that is not yet subject to EU regulation. In recent years, Koch has observed several evasive moves by the industry. “The market is highly regulated,” he says. »And some producers are very resourceful.«
At the Federal Environment Agency (Uba), toxicologist Marike Kolossa recorded traces of the substance. "This case is very unusual," she says. It was assumed that the suspected starting material would not be used in the European Union because no company had submitted an application for approval. "It's detective work."
Reference to cosmetic products
Kolossa and her colleagues' search is helped by the fact that the urine samples were examined as part of the German Environmental Health Study. The participants in this study not only provide urine samples, they are also asked about their habits in an interview. Researchers can look for patterns in the answers. For example, is the burden particularly high among people who frequently consume fast food? Who eat seafood regularly? Who use certain care products?
During their evaluation, the Uba experts found an initial indication of the cause of the poisoning: they discovered an unexpected connection with cosmetic products. “Our first and preliminary suspicion is sunscreen,” says Kolossa. It is still too early to make specific statements about affected products. Kolossa also warns against temporarily avoiding sunscreen because of the suspected case. “Sunscreen protects the skin,” she says. »Giving up is harmful.«
After his findings in the German samples, Bochum toxicologist Holger Koch recently evaluated urine samples collected from Bangladesh, Korea and other Asian countries - without any unusual results. In Denmark, however, increased values were also reported, he says. This suggests that the origin of the problem lies more in Europe.
The Federal Environment Agency is working with other institutes for further investigations in a Europe-wide research network. Suspicious products should now be specifically examined. This may make it possible to find the source - and determine whether a manufacturer is exploiting a loophole or deliberately circumventing European chemicals regulations.
The Germany-wide population study will also collect further data by the end of the year. Kolossa hopes that as many people as possible will take part if Uba asks them to take part in the study. “Anyone who takes part can help solve this puzzle,” she says. “We have to stop this burden as quickly as possible.”