Oil leakage from capsized ship may have serious consequences for river ecosystems of the Lower Danube
"Oil spills are particularly dangerous for the ecosystems of rivers and riparian wetlands with standing water”, said Stoyan Mihov, Freshwater expert at WWF Bulgaria. “Currently river waters are high and have gone into floodplain areas - a major prerequisite for contamination. Petrochemicals break down slowly and their constituents are often more toxic than the oil itself", Mihov said.
Some of the most valuable riparian wetlands in Bulgaria and in the Lower Danube, such as Kalimok Marsh and Srebarna Lake, are situated downstream of Ruse. The ten day delay in disclosing news of the spill may mean that it is already too late to protect these areas.
Petrochemical spills form a thin, monomolecular film on the surface of water. A drop of petrol-based derivative can contaminate one million drops of clean water. The thin layer stops oxygen from penetrating water, causing fish and other aquatic organisms to suffocate.
Oil slicks are particularly dangerous for waterfowl. Birds’ feathers tend to stick and cease to be waterproof. As a result birds die from frostbite or drown because their feathers become heavy with water and oil. The toxicity of petroleum products can also kill birds directly.
WWF continues to monitor the situation.