Pollution of the Danube River

• IDENTIFICATION: European river originating in Germany and generally flowing eastward to the Black Sea

The Danube River, which passes through nine European countries, has suffered severe pollution from both natural and human sources. Maintenance of the river has been difficult because so many nations share its waters, but with the signing of the Danube River Protection Convention in 1994, improvements began.

The source of the Danube is close to that of the Rhine, which flows north, making the pair of rivers a major waterway cutting through Central Europe. The Danube passes through or borders nine countries: Germany, Austria, Slovakia, Hungary, Croatia, Serbia, Romania, Bulgaria, and Ukraine. Because the river’s tributaries also affect other areas, the International Commission for the Protection of the Danube River (ICPDR) includes representatives from the Czech Republic, Slovenia, Bosnia and Herzegovina, Montenegro, and Moldova, as well as the European Union. In addition, the Danube basin includes Poland, Italy, Albania, and North Macedonia, but these nations do not take part in the ICPDR.

The ICPDR was formed to carry out the mandates of the Danube River Protection Convention of 1994: to conserve and improve both surface water and groundwater of the Danube in a rational manner and to oversee the use of the river’s waters. According to the convention, the ICPDR constitutes the overall legal instrument for cooperation on transboundary water management in the Danube River basin. Its missions are to ensure the management of the waters of the river basin and the distribution of those waters in an equitable manner, to prevent hazards from ice and flooding, and to prevent dangerous materials and pollution from entering the Black Sea through the river. The parties to the convention have agreed to take all legal, administrative, and technical measures to maintain—or improve, if possible—the state of the water quality in the Danube and its basin and prevent any damage to the waters. The ICPDR also publishes the magazine Danube Watch, which is intended to inform the public about environmental issues concerning the Danube.

The members of the ICPDR and the members of the International Sava River Basin Commission (the Sava is a tributary of the Danube in southern Europe) issued a joint statement in October 2007, addressing the topics of navigation on the river and the river basin’s ecology. The statement noted both the positive and the negative effects that river navigation can have on the environment as shipping on the Danube replaces road transport. The commission members’ observations fit into a general transportation statement by the European Union covering the ecological impacts of all modes of transportation: road, rail, air, and river.

In 2008, the results of a scientific survey conducted by the ICPDR showed that the river had undergone remarkable improvement since the first such survey was taken in 2001. While the results were positive, the commission’s report on the survey findings emphasized that further work was still needed. Swimming was possible in some areas of the river, but not all. Fish taken from some parts were edible, but further investigation of mercury concentrations was still needed. Although significant populations of plants and animals still existed in the river, and the countries along the river had repaired many damaged areas, pollution of the river by waste plants in such major cities as Belgrade, Budapest, and Bucharest still needed attention.

By 2016, the major threats to the health of the river and its surroundings reportedly came from microplastics (particles of plastic waste), pharmaceuticals, and agricultural runoff. Insufficient data regarding the types of potential pollutants in the Danube hampered pollution mitigation efforts.

The ICPDR continued its work in the 2020s, publishing annual reports, management plans, and an official magazine, Danube Watch. The organization remained committed to researching issues affecting the Danube River, including agriculture, drought, flood, invasive species, ecosystems, and water quality. The DANUBE4all Initiative, launched in 2023, also supports the restoration of the Danube River Basin with funding from the Horizon Europe program. The five-year project aimed to develop a comprehensive, strategic action plan grounded in sustainable and interdisciplinary perspectives.

Although several analyses of fish caught in the Danube River in the 2010s and 2020s found safe levels of mercury and other metals in the edible portions of various fish species, consumer concerns continued. Some research has indicated that mercury levels in Wels catfish, carp, sterlet, pikeperch, European perch, ruffe, and sichel may be the most concerning. Additionally, the location of the fish is also an important factor in determining the risk of mercury contamination.

Bibliography

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Gross, Jenny. “Low Water Levels Disrupt European River Cruises, a Favorite of U.S. Tourists.” The New York Times, 29 Aug. 2022, www.nytimes.com/2022/08/29/travel/river-cruises-drought-europe.html. Accessed 19 Sept. 2025.

"The International Commission for the Protection of the Danube River (ICPDR) Celebrates World Water Day 2025: 'Save Our Glaciers'.” United Nations, 21 Mar. 2025, unis.unvienna.org/unis/pressrels/2025/unisous446.html. Accessed 19 Sept. 2025.

Jansky, Libor. The Danube: Environmental Monitoring of an International River. United Nations UP, 2004.

Magris, Claudio. Danube. Translated by Patrick Creagh. 1989. Farrar, Straus and Giroux, 2008.

McGrath, Stephen. "Dirty Danube: Looming Pollution Threats to the World’s Most International River." The Guardian, 13 Nov. 2016, www.theguardian.com/sustainable-business/2016/nov/13/danube-looming-pollution-threats-worlds-most-international-river-microplastics-fertiliser. Accessed 19 Sept. 2025.

Murphy, Irene Lyons, editor. Protecting Danube River Basin Resources: Ensuring Access to Water Quality Data and Information. Kluwer Academic, 1997.

"Shared Waters--Joint Responsibilities: ICPDR Presents Annual Report 2021." ICPDR, www.icpdr.org/main/shared-waters-joint-responsibilities-icpdr-presents-annual-report-2021. Accessed 19 Sept. 2025.

Simionov, Ira-Adeline, et al. “Human Health Risk Assessment of Potentially Toxic Elements and Microplastics Accumulation in Products from the Danube River Basin Fish Market.” Environmental Toxicology and Pharmacology, vol. 104, 2023, p. 104307, doi:10.1016/j.etap.2023.104307. Accessed 19 Sept. 2025.