New insights: How harmful is microplastics for people and the environment?

New insights: How harmful is microplastics for people and the environment?
Photo: Andrey Nekrasov/Zuma Press/dpa, Arne Dedert/dpa

Microplastics in our brain – and now also in our plants? Researchers warn of new risks of health and the environment.

Microplastics refer to tiny plastic particles with a size between 1 micrometer and 5 millimeters that are widespread in the environment. Depending on the definition, gel -shaped, wax -shaped or liquid polymers are also included. Even smaller particles are referred to as nanoplasty. These particles are created either by the decay of larger plastic objects (secondary microplastics) or are specifically manufactured for products such as cosmetics (primary microplastics).

Little is known about distribution and risks, but many studies are in the process of changing. The results are often still subject to uncertainty – nevertheless you can provide knowledge or indicate important problems.

You can find the latest results here:

  • Microplasty hinders photosynthesis
  • More microplastics in human brain
  • Microplasty affects mouse brain
  • What we know for sure

The latest findings: microplastics should hinder photosynthesis in plants

Microplastics may significantly reduce the ability of plants for photosynthesis. This is shown by a new study that was published in March in the journal “Proceedings of the National Academy of Sciences USA” (PNAS). The researchers found that microplastics can reduce photosynthesis performance of different plant species by 7 to 12 percent. Important crops such as corn, rice and wheat, but also algae in the sea and in fresh water are particularly affected.

The meta study has evaluated 157 empirical studies from the last two decades and explains the effect as follows: microplastic particles would reduce chlorophyll content in plants, which the pigment need for photosynthesis processes.

This could have serious consequences: farmers could expect harvest losses of 4 to 13.5 percent over the next 25 years. Fishing would also be affected because microplastics inhibit the growth of algae, which form the basis of many food chains. In addition, climate change could be reinforced. Plants usually store carbon dioxide from the air, but if they operate less photosynthesis, more COâ‚‚ remains in the atmosphere.

The study results alert – however, there is also criticism of the study. Elke Brandes from Johann Heinrich von Thünen-Institut, Braunschweig doubts the results. “There is simply too little knowledge and data in this research field to justify a meta -analysis as it was carried out here”, it is cited by several media. The assertion that microplastics in arable soils are currently leading to significant loss of yield lacks a sufficient scientific basis.

February 2025: More microplastics found in the human brain

A American research team found significantly more nano and microplastics in the liver and brain of deceased people who were examined in 2024 than in rehearsals from 2016. The burden in the brain was particularly high-up to 30 times higher than in liver or kidney, reports the group around Matthew Campen from the University of New Mexico in the specialist journal “Nature Medicine”. Her study was published in February – Utopia reported.

With a chemical analysis, the team also determined the composition of the plastic. They found polyethylene most often used for foils and bottles. It accounted for 40 to 65 percent of the plastic in the liver and kidney, even 75 percent in the brain.

Microplastic particles on a index finger
Microplasty is everywhere: These larger particles were found on the Warnow bank in Mecklenburg-Western Pomerania. (Photo: Bernd Wüstneck/DPA central picture/dpa)

The burden on twelve brain samples from 2019 to 2024 was particularly high for people with a proven dementia: they contained between 12,000 and 48,000 micrograms of plastic per gram. However, the research group emphasizes that its study does not demonstrate a direct cause-effect relationship: “This data is associative and do not show the causal role of such particles in health impairment.”

Some differences in the brain samples could also be attributed to geographic differences, since the samples were taken from New Mexico and on the other hand on the east coast of the USA.

January 2025: Neurological problems in mouse brains

In January, a group around Haipeng Huang from the Chinese Research Academy of Environmental Sciences presented in Beijing Research results, according to which microplastics may clog blood vessels in the brain of mice. The affected mice moved less, could be more oriented and are less persistent, the study said. However, the results are not easily transferable from the mouse due to differences in the brain structure to humans, the study authors wrote in the journal “Science Advances”.

What we know: How dangerous is microplastics for people and the environment?

According to the Federal Intutut for Risk Assessment (BfR), humans can come into contact with microplastics, including breathing air, food, cosmetics and drinking water. According to the office, there has been no reliable knowledge about the effect of microplastics on humans. Nevertheless, the topic remains relevant, since plastic is hardly dismantled in the environment and continues to accumulate. Research is still at the beginning with many questions.

The BFR refers to studies that show that larger particles are usually excreted undigested. However, very small particles could get into the bloodstream. It is still unclear whether this long -term effects have negative effects. In addition, microplastics can bind pollutants from the environment, but a model calculation by the European Food Safety Authority (EFSA) suggests that the contribution to the overall burden on humans is low. Long-term studies are currently also running to better assess the risks of microplastic recording over the air.

The microplastic problem does not only affect people. For example, the fabrics get into the environment via the wastewater or sewage sludge. The plastics have also been detected in the gastrointestinal tract of animals-here too, the health effects are largely unclear. Animals absorb microplastics, for example, through food or water, and thus often various other pollutants. Sea organisms such as mussels and fish are particularly affected.

With material of the dpa

Read more on utopia.de:

  • Record less microplastics: Scientists give concrete everyday tips
  • 11 tips to avoid microplastics from clothing: this is how you do it right
  • Hamburg breathes microplastics: This source pollutes the air the most

** marked with ** or orange underlined Links to sources of supply are partially partner links: If you buy here, you will actively support Techzle\.com, because we will then receive a small part of the sales proceeds. More information.

Recent Articles

Related Stories