Geneva (dpa) - The occurrence of microplastics in drinking water and its possible health effects must, according to the World Health Organization (WHO), be further investigated.
That applies to the distribution of these particles and also for the risks, the WHO announced on Wednesday in Geneva. "Based on the limited information available, microplastics in drinking water does not appear to present a health risk at current levels," said WHO expert Maria Neira. Other contaminants of the water are from today's view much more significant, said WHO expert Bruce Gordon.
In any case, it is important to broaden the knowledge base and, above all, to stop the growth of the global plastic garbage mountain. "Microplastic is everywhere in the environment, including in the water cycle," says the WHO report.
The origin of the microplastics in drinking water is often unclear. Important sources are rain or meltwater and sewage. All in all, however, the available studies are too incomplete to be able to determine more precisely the respective extent of these inflows or to grasp the sources more precisely. "In addition, pollution can also occur in other processes such as treatment, distribution and bottling."
In 2017, around 348 million tonnes of plastic were produced worldwide, excluding fiber production. This amount is set to double by 2025 in the face of population growth, consumption and disposable behavior, and is likely to triple by 2050, WHO estimates. The market is huge. In Europe alone, 60,000 companies with 1.5 million employees and a turnover of 355 billion euros produced plastic.
With proper cleaning, the wastewater can be cleaned by 90 percent of the microplastic. The same applies to the treatment of drinking water, WHO continued. The problem is that a large part of the world's population currently does not benefit from adequate water and wastewater treatment.
The environmental doctor Hanns Moshammer from the Medical University of Vienna also shares the call for more research, especially with regard to the possible effect of microplastics over 150 micrometers. "Healthy skin or mucosa is actually a very efficient barrier to larger particles." There is a need for research on the barrier behavior of diseased skin or mucous membranes - for example after injuries or inflammation.
Recently, a research team headed by the Alfred Wegener Institute (AWI) in Bremerhaven reported that microplastic particles trickle from the air onto the earth's surface in the snow - even in the remote Arctic. The tiny particles are transported in the atmosphere and can be distributed over long distances.
According to Australian researchers, people consume microplastics every day - through food, drinking water or just breathing. Up to five grams of the tiny particles come into the body every week - depending on the circumstances. A credit card weighs about five grams. The study is based on data on microplastic - particles smaller than 5 millimeters - in the air, in drinking water, salt, beer and shellfish.
Significantly less microplastics have been detected in German tap water than in mineral water, said Martin Wagner of the Norwegian University of Science and Technology (NTNU) in Trondheim. It can be assumed that sewage treatment plants remove most of the plastic particles. "The problem here is that the microplastics will then be in sewage sludge and re-enter the environment when sewage sludge is used for fertilization in agriculture." About the health impact of microplastics can not make general statements.