Red alert: Mercury pollution in rivers is increasing dramatically!

Red alert: Mercury pollution in rivers is increasing dramatically!

An alarming increase in mercury compounds in rivers around the world has recently been detected. These substances are powerful neurotoxins that endanger human health, particularly through fish consumption. Global mercury inputs into rivers have not been well documented, while previous studies have largely focused on mercury concentrations in the atmosphere, soils and seawater. Researchers have now developed a model to quantify the pre-industrial export of mercury from rivers into the oceans. As the Small newspaper reported, the estimated mercury input for the year 1850 was around 390 tons annually. This value is currently almost 1,000 tonnes per year.

The increases in mercury inputs are particularly pronounced in South Asia, Southeast Asia and North and South America. In the Amazon region, over 200 tons of mercury are released into the waters every year, primarily through human activities such as small-scale mining. These dramatic changes are directly linked to deforestation, which increases soil erosion and thus further increases mercury levels.

Origin of mercury from industrial activities

In Germany, coal-fired power plants emit over five tons of mercury into the air every year. These emissions enter water bodies that are already heavily polluted through rain. According to that NABU All German rivers exceed the limit values ​​of the Environmental Quality Standard (EQN) for mercury. Predatory fish in rivers such as the Rhine, the Elbe and the Danube, which have had high levels of pollution for more than 15 years, are particularly affected.

The organic compounds in mercury, especially methylmercury, are particularly toxic and damage nerve tissue. Pregnant and breastfeeding women are therefore recommended to avoid certain types of fish such as eel or pike. NABU is urgently calling for stricter requirements for the limits of coal-fired power plant emissions in order to reduce the negative effects on the environment and health.

Health risks and international measures

Mercury is known to damage the central nervous system, immune and reproductive systems. Unborn children are particularly at risk. That's why US authorities advise pregnant women to avoid certain types of fish from contaminated areas. At the international level, there are already several agreements regulating mercury use, including the OSPAR Convention and the international Minamata Convention, which is expected to enter into force in 2017. Studies and projects like those of Öko-Institut, research the effects of mercury and possible mitigation techniques.

The project, which is being carried out under the leadership of the Federal Environment Agency and the Oeko-Institut, aims to develop a national mercury strategy for German industry. Even though cost-effective methods exist to reduce mercury emissions, the problem remains because there are no permanent “mercury sinks” that can permanently remove mercury from the environment.