Danube Watch 2/2019 - What is the Magic Silver Box Telling Us?

With an increased concern about the presence of micro-plastic contaminants in global water sources ranging from the oceans to rivers to lakes around the world, there is a more urgent need for testing.

A study in the Austrian stretch of the Danube River led by the Environment Agency Austria revealed a certain contamination of micro-plastics and other studies show that micro-plastics are ubiquitous in freshwater systems. Pollution is a transboundary issue and needs to be tackled at an EU (or even global) level. For these reasons, it was necessary to include micro-plastics in the recent fourth Joint Danube Survey (JDS4). With this investigation, consistent data along the entire river and some of its tributaries will be produced to get a first baseline overview of both micro-plastic contamination within the Danube River and of the real pressure on the environment.

Regarding JDS4 itself, there will be a more active role for national authorities to carry out monitoring. This enables participating countries to further engage with the project, adopting new, innovative and tailor-made approaches that work best for them. It is expected that this approach will lead to a more flexible and effective process and, most importantly, to better results. We want to foster more coordination and even more improvements for JDS, helping countries to share their experiences, exchange ideas and harmonise their processes.

The surveys were conducted along the entire river at 15 sampling sites that have been chosen by the participating countries (Germany, Austria, Slovakia, The Czech Republic, Hungary, Serbia and Romania) to measure the presence of micro-plastics. Samples were taken by means of passive samplers, which were originally designed for the sampling of suspended particulate matter. By this principle, suspended material is allowed to settle in a specialised box that has been placed in the river which can be analysed later on. This analysis will be carried out in a centralised location. Sampling for micro-plastics in Austria was carried out by experts from the Environment Agency Austria and the Austrian activities were coordinated by the Ministry for Sustainability and Tourism. Samplers were developed and built by funds of the German Environmental Agency and ownership has graciously been transferred to the users.

At this stage, the results of this investigation are not yet available. Therefore, we do not know the precise nature or concentration of the plastic and micro-plastic contaminants in the Danube. The material which has been collected was made up of very fine particles indistinguishable to the naked eye from other natural material. From a previous study, carried out by the Environment Agency Austria on behalf of the Ministry for Sustainability and Tourism, we know that micro-plastics are found in the entire water column. Larger items can be stopped and removed by hydropower plants, others pass through and generally end up at the river banks.

There are several main sources of micro-plastic contamination. One way these contaminants enter the river system is due to the fact that micro-plastics are deliberately added to consumer products like cosmetics and detergents and then make their way into waterways through wastewater. Another way is abrasion of tires and road particles or the result of industrial processes such as production, conversion and transportation, loss of artificial turfs or construction sites and finally secondary micro-plastics which break away from degraded plastic waste in the environment.

One important aspect of testing is determining where the highest concentrations of micro-plastics appear in the Danube. We do not have clear data on whether the concentrations of these materials differ between urban, rural and industrial stretches of the river yet but do expect to get answers through this survey. However, urban areas and areas with high anthropogenic activity (roads etc.) are, of course, prone to having higher concentrations of plastics and micro-plastics in general.

JDS4 also hopes to get a better understanding of what the proportion of micro-plastics as a part of general plastic pollution is. Generally speaking, around 5-13 Million tons of macro- and micro-plastics enter the oceans annually on a global scale, of which 1.5 Million tons are micro-plastics. In the EU, some 75,000 to 300,000 tons of micro-plastics are emitted into the environment every year. Almost all of the micro-plastics come from land-based sources via run-off or waste water treatment, which end up in rivers and, ultimately, reach the oceans. Rivers are major contributors to marine micro-plastic levels and this fact is why the data currently being collected and analysed is critically important.

Once the samples have all been tested and the data analysed, the results will be able to be put to use to inform current river management and environmental policies. At the EU level, the Network of Environment Agencies has already contributed actively to the development of the EU Plastic Strategy, a vehicle to reduce plastic leakage into the environment. The Environment Agency of Austria has already contributed to the strategy within the Network of European Environment Agencies and will assist with its full implementation.

Moreover, reports on bio-plastics and on littering have been developed to assist the European Commission in its decision making processes. Results have been disseminated in dedicated conferences addressing all stakeholders along the value chain. The Environment Agency of Austria will take a leading role in the network and continue consulting with the European Commission.

Further steps that could add to a collective solution to the very serious threat that micro-plastic contamination poses are varied but very achievable with concerted and coordinated efforts. Waste management in countries with less developed systems should obviously be improved. European industry is encouraged to transfer knowledge, technology and good practices to other industrial sites, thus addressing the global market and increased producer responsibility. Adding to this, the concept of a circular economy as leverage to reduce plastic emissions into the environment is a promising idea. By closing the circle, waste would be re-integrated into the value chain and therefore emissions to the environment would be reduced.

Littering appears to be a relevant source of plastic entering the environment. Anti-litter actions need to be implemented by waste associations in order to prevent waste and litter from entering the environment through the careful use of resources. Austria's planned 2020 ban on plastic grocery bags is another example of how to help prevent plastic litter from entering the environment.

Regarding traffic and tire wear as well as building/construction, need for action has been identified and appropriate measures have to be developed.

Finally, a ban of micro-plastics as primary materials would be necessary. The European Chemicals Agency (ECHA) is about to propose such restrictions on the use of micro-plastics intentionally added to consumer products.

Through the combined efforts of research and action, the threat of micro-plastic contamination can be addressed and, eventually, solved in a sustainable way. National and international actors across the Danube River Basin are working together toward this goal and the conclusions drawn from JDS4 will provide the knowledge needed to direct informed action.