When it comes to microplastics, the focus is often on the oceans. But the substances also occur in freshwater. Researchers have just discussed this problem at a three-day conference that ended on Wednesday in Paris. The experts’ recommendations to politicians are to be incorporated into the UN water conference, which will take place in New York at the end of March. The coordinator of the conference, which was co-organized by UNESCO, was environmental researcher Christian Laforsch from the University of Bayreuth.

What is meant by microplastics?

Microplastics are tiny plastic particles or pieces that are either manufactured in microscopic sizes for personal and industrial use or come from discarded plastic items. Microplastic pollution is considered a potential threat to ecosystems and society.

How massive is the pollution of water bodies by microplastics?

The researchers are not yet able to record this precisely, explained Laforsch. Microplastics end up in fresh water and on farmland as improperly disposed of waste, as abrasion from tires or when insulating material is cut to size. By default, scientists can analyze particles down to a size of ten micrometers, about a tenth the diameter of a hair. However, plastic breaks down into even smaller particles that cannot yet be detected. So far, pollution has only been the tip of the iceberg.

What is the particular problem when plastic particles end up in the water?

Unlike chemical substances, which are usually evenly diluted in water, plastic particles are deposited in different areas as sediment in water bodies or float on the surface. In this respect, it is not possible to say in general what the effects of pollution are. The nature of the particles is also different, and the chemicals they contain can be dangerous.

From the point of view of the researchers, how should politics react to the pollution of the environment by microplastics?

According to the experts in Paris, efforts to protect water must not only take into account the oceans, but also the ecosystem on land. Regulations relating to plastic and the protection of bodies of water, such as the EU Water Framework Directive, should be adjusted accordingly.

What must the industry do?

The industry must be obliged to disclose the ingredients that are added to a plastic product during the production process, for example to change its nature. “What’s in there anyway?” This is sometimes not clear at all, said Laforsch.

Does it help to use other plastics than before?

The use of sustainable and environmentally friendly plastics is one of the demands formulated by the experts in Paris. Even when designing products made of plastic, it is necessary to consider what will become of them at the end of their use cycle. It’s not just about disposal and recycling. In order to achieve better protection of water from microplastic pollution, industrial processes would have to be changed and technical innovations needed.