Following Russian attacks on December 20th on sunflower oil storage facilities at the port of Pivdenny near Odesa, tanks were damaged, triggering significant and potentially damaging marine pollution. Witnesses reported that the vegetable oil quickly covered neighboring areas, and soon reached the Adzhalik estuary. Unfortunately, the spill was not contained within the estuary in time; by December 24th, the oil spill had reached the shoreline within the city of Odesa. The pollution has affected waterbirds, with around 300 birds reported to be rescued and taken to the Odesa Zoo for rehabilitation.
What does it mean for wildlife? In its initial stages, while liquid, a spill of food oil stays at the top of seawater. This results in smothering and coating in a physical way similar to a fossil fuel spill, though it is not as toxic if ingested. Wildlife suffers physical effects becoming coated with the oil that can result in death through hypothermia, dehydration, diarrhea, starvation, or suffocation from the clogging of nostrils, throats, or gills. Often the numbers of birds rescued is just a fraction of the total numbers lost.
What to expect? Vegetable oil normally breaks down more quickly as bacteria and fungi can metabolize it more easily than crude or refined fossil oils. However, the speed depends on the temperature; at winter temperatures, sunflower oil can congeal and partially solidify, slowing the breakdown and prolonging the physical impacts. If it does break down in the sea, it will consume oxygen from the water, resulting in a reduction of oxygen available for fish and other aquatic fauna.
After polymerization, oxidation, or mixing with debris, vegetable oils become denser than water. They sink to the seabed and form a layer on the sediment that can smother bottom-dwelling species and cut off oxygen there for some time. This can be accelerated by contact with salt water and debris and by partial breakdown as the fats and oils congeal at low temperatures (like fatbergs in sewers).
According to NOAA, a marine spill of sunflower oil that sinks and forms a cap on benthic (seafloor) habitats, as well as concrete-like lumps in intertidal sandy sediments, can persist for more than 6 years. At the same time, unpolymerized vegetable oils (which could be the case if an accident happened in summer) biodegrade rapidly and completely, even under anaerobic conditions. Thus, to answer what to expect, research should be conducted to determine if polymerization has occurred.
What should be done? Although not having the same toxicity as fossil oils, large food oil spills can be very harmful and need a similar containment response as regular oil spills. We can’t evaluate if the relevant Ukrainian authorities had the possibility for a more effective and timely response, but certainly, this massive accident would not have happened were it not for the Russian attacks. Now the spread of pollution should be stopped as soon as possible, the oil should be removed to the greatest extent possible, and then remediation measures should be implemented for marine and coastal ecosystems. Now relevant Ukrainian authorities should prioritise not only mitigating consequences of this accident, but also effective preparation for other similar cases in future.
Photo Новини live
