Microplastics in water
Along with climate change, the spread of microplastics is one of the greatest human interventions in the natural environment. Plastic parts have spread all over the world. They can be microscopically small or appear as visible particles that can be seen with the naked eye. They exist in the deep sea, in remote polar regions, in the atmosphere and in the bodies of humans and animals. Water also contains microplastics in varying concentrations and thus reaches the consumer. The consequences of microplastics for health and the environment are still being researched. But what is microplastics actually, and how can we protect ourselves from microplastics in water?
What is microplasty?
Microplastic was discovered in 1997 by Charles Moore, an environmental activist who discovered countless small plastic particles between plastic parts in the "Great Pacific Garbage Whirlpool".
Today, the term microplastics is mainly used in relation to the size of certain plastic parts. Microplastics are plastic particles that are smaller than five millimetres.
There are also plastic particles whose sizes are in the microscopic range as microparticles and nanoplastic particles, but which are not present at molecular size.
With regard to the types of microplastics, questions of demarcation are discussed, which are an important topic for research today. Microplastics must basically be understood as a collective term for parts made of plastics. Basically, polymers, especially polyethylene, are counted among the materials from which microplastics can be created.
The plastics are used for the production of a wide range of everyday products, from car tires to clothing and cosmetic products. Depending on how it is created, a distinction is made between primary and secondary microplastics.
How is microplasty created?
Primary microplastics refers to so-called base pellets, which are the starting material for numerous products such as toothpaste or cleaning agents. Here, small plastic particles are deliberately produced as material. Especially cosmetics, for example peelings, contain microplastics. However, these particles are also used in cleaning jets and medicines.
Secondary microplastics is an unwanted product that is created by chemical and physical processes. For example, UV light decomposes plastic, but also the daily abrasion of car tires produces microplastics. According to the German Federal Environmental Agency, fleece clothing made of synthetic fibres can lose up to 2000 of these fibres per wash cycle, which then ends up in the waste water.
Microplastics in the environment
Since plastic is ubiquitous, from packaging material to children's toys, plastic waste and plastic particles are released into the environment in many ways. It is estimated that mankind has produced some 8.3 billion tons of plastic since the invention of plastic. 1
According to a study by the Fraunhofer Institute for Environmental, Safety and Energy Technology UMSICHT, up to 330,000 tons of microplastics are released every year in Germany alone. This figure only refers to the primary microplastics mentioned above.
Microplastics cause special problems due to their basic properties: It is very difficult to degrade and will therefore accumulate in oceans, the ground and even in the air. Microplastics often have a similar size to pollen grains. This lightness means that microplastics are transported over long distances in the atmosphere.
Microplastics from Europe can be found both in the Arctic and in the Alps. Especially the snow washes the microplastic out, so that it can be found in practically all polar regions. Microplastics can also be found in the deep sea. This leads to serious health problems for marine organisms.
Why is microplasty so dangerous?
Microplastic particles are ingested by animals and lead to mechanical injuries (for example in the intestine and stomach), tissue changes and symptoms of poisoning. The microplastics also enter the food chain via the animals and thus also enter the human diet. At present, intensive research is being carried out into the consequences for humans, animals and the environment, as it is only possible to prove some effects, but a large number of other possible effects are suspected. One is warned by other pollutants such as asbestos, whose dangerousness was also only recognized in the course of time.
This is precisely why the presence of microplastics in the air is a cause for concern: studies show that a not insignificant proportion of the particles are absorbed via the respiratory tract. Since it is similar to fine dust, diseases of the lungs, heart and circulation as well as cancer are to be feared.
A major problem is above all the damage to the environment caused by enrichment with plastics and microplastics, as this also increases climate change, for example. Microplastics contribute to the input of the very effective greenhouse gas methane. A diseased environment has repercussions on humans. Microplastics in water also plays a role in this context.
How does microplastics get into the water?
The ways in which microplastics get into the water and also into tap water have not yet been fully researched. However, practically every private household contributes to the spread of microplastics. Every time a sweater containing polyester is cleaned, microplastics are rinsed out. Due to the daily abrasion of car tires, enormous amounts of microplastics also get into the water - especially after rainfall. Currently, wastewater is insufficiently filtered by microplastics.
As Martin Wagner from the Norwegian University of Science and Technology (NTNU) in Trondheim found out, microplastics are returned to the water cycle through sewage sludge that is spread on fields in agriculture.2 However, microplastics also play an important role, as they enter the water via detours. Often the particles first get into the atmosphere through abrasion processes and later into the water through rain and snow.
How much microplastic is in the water?
A large-scale investigation by the Alfred Wegener Institute (AWI) in 2014 revealed that between 86 and 714 microplastic particles were present in one cubic metre of water. Almost all German sewage treatment plants are hopelessly overtaxed with microplastics. Depending on the size of the plant, between 93 million and 8.2 billion particles of microplastics would enter our rivers. (Ingenieur.de).
Is there microplastics in our drinking water?
Yes, a study by the University of Minnesota in cooperation with the non-profit journalist network Orb Media analyzed 159 drinking water samples worldwide. 80 percent of the water samples contained microplastics, although the proportion in Germany is considerably lower than in other countries. In one liter of water, two and a half particles floated in samples from Hamburg and Dortmund. Further representative investigations are urgently needed.
What are the health consequences of microplastics in water?
The World Health Organization (WHO) has taken a position on this question in 2019 and has compiled the results of 50 recent studies. For scientific standards this is rather a thin basis. For this reason, the conclusion of the WHO that "based on the limited information available, microplasty in drinking water at the current level does not represent a health risk" (WHO expert Maria Neira) is very questionable and of a provisional nature.
Although it is assumed that large microplastics are excreted by humans through digestion, particles smaller than 1 micrometer could penetrate cells. This can then lead to inflammatory processes, says Professor Werner Kloas from the Leibnitz Institute of Aquatic Ecology and Inland Fisheries in Berlin.3
It is also very likely that other harmful substances will be increasingly spread via microplastics. This is due to the so-called "hydrophobic property of the plastic molecules": environmental toxins such as dioxin can attach themselves to the non-polar microplastics just as well as bacteria, which can form a biofilm on microplastics and then attract other bacteria. A study by the Alfred Wegener Institute (AWI) has already proven that "pathogens use microplastics as a means of transport".4 The European Food Safety Authority wants to further clarify this fact, in particular the question of whether carcinogenic aromatic hydrocarbons (PAH) are also transported with the microplastic particles. The WHO also announced further research.5
Both the Federal Institute for Risk Assessment and the European Food Safety Authority are demanding more data in order to be able to set a limit value for microplastics in the future.6
What can be done as an individual against microplasty?
It goes without saying that more sustainable consumer behaviour contributes to the reduction of plastic. But it is not that easy to avoid the ubiquitous plastic. It is helpful, for example, to buy higher-quality clothing with more expensive polymers that use less plasticizer. When it comes to drinks, glass bottles should be used instead of plastic. A special role is played by cosmetics with their primary microplastic particles. Here, consumers can make sure that the chosen articles do not contain peeling beads.
Overall, the consumer magazine Test advises the following measures:
- Rare driving
- Dispose of plastic properly
- Avoid cosmetics with microplastics; see Bund-Einkaufratgeber (7)
- Buy higher quality clothes
- Wash as short and cold as possible
- Prefer shops without packaging; see Zerowastemap (8)
What techniques are there to filter microplastics from the water?
Water filters can effectively remove microplastics from the water. There are different ways to get the microplastics out of the drinking water. However, it is necessary to differentiate between the size and nature of the microplastics and to distinguish where and how it is filtered.
Find out more in our article on how microplastics can be filtered out of water ...read more.
Related articles and products
- Sciencemag: "Production, use, and fate of all plastics ever made" WWW: https://advances.sciencemag.org/content/3/7/e1700782.full (19.07.2017)
- Spiegel: "How dangerous is microplastics in drinking water?" WWW: https://www.spiegel.de/gesundheit/ernaehrung/mikroplastik-in-trinkwasser-wie-gefaehrlich-ist-das-who-legt-bericht-vor-a-1283051.html (August 22, 2019)
- IGB-Berlin: "Underestimated danger: microplastics on dry land" WWW: https://www.igb-berlin.de/news/unterschaetzte-gefahr-mikroplastik-auf-dem-trockenen (05.02.2018)
- Helmholtz: "Why is microplastics harmful? WWW: https://www.helmholtz.de/erde_und_umwelt/warum-ist-mikroplastik-schaedlich (16.11.2018)
- Test.de: https://www.test.de/Mikroplastik-Wie-gefaehrlich-sind-die-winzigen-Kunststoffteilchen-4817845-0/
- SWR: https://www.swrfernsehen.de/marktcheck/broadcastcontrib-swr-7460.html
- Federation: https://www.bund.net/fileadmin/user_upload_bund/publikationen/meere/meere_mikroplastik_einkaufsfuehrer.pdf
- Zerowaste Map: https://zerowastemap.org