In brief
A container ship carrying lithium‑ion batteries and light fuel oil was struck by three maritime drones east of Cape Kaliakra and sank around midnight on 28 October 2026. Bulgarian authorities performed seawater sampling at multiple coastal sites and in the vicinity of the wreck to detect petroleum products, polychlorinated biphenyls and metals. The incident highlights the growing use of drone attacks in the Black Sea and the need for rapid scientific assessment of marine pollution.
A container vessel destroyed by three maritime drones sank near Cape Kaliakra on the night of 28 October, prompting Bulgarian authorities to launch a comprehensive seawater sampling program aimed at detecting potential environmental contamination. The ship, identified as the CONTSHIP JET, was reported to have carried lithium‑ion batteries and 421 containers of various fuels, including light gas oil that is expected to evaporate quickly in open water.
The event took place roughly 21 nautical miles southeast of Shabla, and all 18 crew members—14 Filipinos and four Ukrainians—were rescued and transported to Varna. While maritime drones reportedly detonated on the vessel’s hull, the ship sank around midnight without any visible signs of pollution noticed by Defence Ministry teams that initially collected samples from two sites in Bulgarian territorial waters.
In response, the Executive Environment Agency’s regional laboratories in Varna and Burgas were mobilised to conduct detailed chemical analyses. Samples were collected at five coastal locations—Durankulak, Shabla, Cape Kaliakra, Byala and Sozopol—on 29 October by teams from the Black Sea Basin Directorate and the Environment and Water Ministry, according to a statement from the Ministry.
Analytical protocols focus on measuring petroleum hydrocarbons, polychlorinated biphenyls (PCBs), heavy metals, and key physicochemical markers such as pH, dissolved oxygen and turbidity. PCBs are a class of persistent organic pollutants that can accumulate in marine organisms, posing long‑term ecological risks. Heavy metals, including zinc, copper and lead, are monitored due to their potential toxicity to aquatic life. Petroleum hydrocarbons are detected using gas chromatography‑mass spectrometry, a routine technique that can identify specific compounds such as gasoline, diesel and oil residues even at low concentrations. The comprehensive data set will allow comparison to baseline levels established by previous monitoring projects in the Black Sea, thereby revealing any anomalous trends that visible inspection may miss.
Experts from the Maritime Administration Executive Agency emphasised that the vessel’s cargo of gas oil is “expected to evaporate rapidly” and “not reach the Bulgarian coast,” indicating that, at the time of reporting, no significant immediate marine or coastal damage was anticipated. However, the 20 containers that fell overboard might still pose a localized risk, necessitating continued surveillance and potential remediation actions if necessary.
Admiral Emil Eftimov, Bulgaria’s outgoing Chief of Defence, commented on the origin of the drones. “We are not at war. The drones did not enter territorial waters, so we did not take action,” he said in an interview aired on bTV. The admiral highlighted that the drones “came from the east” and that Bulgaria’s intelligence and early‑warning systems have been strengthened in light of recent tensions in the region.
Monitoring will continue with periodic seawater sampling to generate a time‑series dataset that can be analysed against regional environmental baselines. The Executive Environment Agency plans to release the results publicly to ensure transparency and to support scientific research on the impacts of maritime drone attacks on coastal ecosystems. This incident underscores the intersection of emerging drone technology, maritime security, and marine environmental stewardship, illustrating how rapid, data‑driven assessment is essential in the face of novel threats to ocean health.
