The Ministry of Transport and Communications and the Executive Agency “Maritime Administration” inform the public that the tar deposits observed over the past few days on beaches along the northern and, particularly, the southern Black Sea coast are so-called tar balls – hardened, tar-like lumps formed from aged petroleum pollution that has been present in the marine environment for an extended period. They were washed ashore by waves together with marine debris following rough sea conditions between June 15th and 20th.
These deposits are not traces of a fresh oil spill. They consist of residual heavy fractions of crude oil or petroleum products that have undergone natural weathering processes over time, including evaporation of light components, dispersion, oxidation and biodegradation. In colder water they solidify and sink, while in warmer conditions they soften and rise to the surface, often adhering to seaweed or other floating debris.
Due to the significant changes in the chemical composition and physical characteristics of the substance, it is not possible to determine its age or specific source. This makes it practically impossible to identify a vessel responsible for the pollution. Tar balls of this kind can travel considerable distances, including across national boundaries, before being washed ashore.
This is not a precedent – similar deposits have been observed in previous years. The matter involves aged pollution originating outside Bulgaria’s territorial sea, the exact source of which cannot be conclusively established. It is important to note that pollution from petroleum-based products was also recorded along the southern coast of Romania during the same period.
Within the scope of its mandate, the Executive Agency “Maritime Administration” carries out continuous monitoring of vessels in Bulgarian ports, as well as satellite surveillance of maritime areas for possible spills. To date, there is no evidence of an ongoing or recent oil spill in the territorial waters of the Republic of Bulgaria, nor of any recent maritime incident in the region that could have caused the pollution observed along the Bulgarian coastline in recent days.
The Ministry of Transport and Communications will continue to work in cooperation with the Ministry of Environment and Water, the Ministry of Tourism and local authorities to ensure that the debris washed ashore is cleaned up promptly and removed without disruption to the tourist season.