A handful of sewage hotspots damage coastal ecosystems

In 10 seconds? Human wastewater is one of the biggest polluters of coastal ecosystems, with more than 80% of sewage released untreated into the environment. A new study pinpoints the just two dozen locations that play a role in the emergence of “dead zones” in the oceans.

What’s the problem? While it’s easy to flush and forget, untreated sewage is causing a multitude of problems. Sewage can increase the concentration of nitrogen in coastal waters, notably in coral reefs, alongside transporting a variety of pathogens, pharmaceuticals, and heavy metals, which all negatively impact marine life. A new study shows that half the amount of global sewage pollution comes from just 25 locations. Among the biggest offenders the authors mention the Yangtze River in China, the Nile in Africa, the Mississippi in the US, the Paraná in Argentina, and the Danube in Europe.