How POLITICO Used Cerulean to Expose Oil Pollution from Sanctioned Tankers

A new investigation by POLITICO and SourceMaterial using SkyTruth’s Cerulean oil slick monitoring platform found that at least five sanctioned Russian tankers have continued operating in European waters after leaving oil slicks behind. The investigation is one of the first to directly link environmental damage from the “shadow fleet” to visible pollution at sea.

These findings highlight a growing and underreported threat. As sanctions tighten, more tankers are operating outside international norms, increasing both environmental and legal risks. Cerulean’s new sanctioned vessel tracking capability was designed to shed light on this hidden pollution, helping journalists, policymakers, and the public connect the dots between sanctions evasion and environmental harm.

How Cerulean Tracks Oil Pollution from Sanctioned Vessels

To date, SkyTruth has identified over 30 sanctioned vessels associated with likely oil slicks worldwide, which you can now view in our Cerulean application by following this link or by selecting “Sanctioned” from the “Filter by Tag” menu.

Cerulean matches vessel IDs from our slick detections against TankerTrackers’ “Official Blacklisted Tankers” database, which compiles sanctioned vessel lists from international authorities and watchdogs including the UN, EU, US Treasury’s Office of Foreign Assets Control (OFAC), UK’s Foreign Commonwealth & Development Office, Australia’s Sanctions Office, United Against Nuclear Iran, and Global Anti-Corruption (UK).

Real-World Consequences

In December 2024, two aging Russian tankers, Volgoneft-212 and Volgoneft-239, were wrecked in a storm near the Kerch Strait. Volgoneft-212 broke apart and sank, and the Volgoneft-239 ran aground. Together they spilled thousands of tons of fuel oil, polluting more than 60 km of coastline. Neither vessel should have been operating in the region. One had its license suspended just weeks earlier, and neither was certified to operate in the Kerch Strait in the winter. Cleanup costs could reach into the billions of dollars.

APUS (IMO 9280885), another example, is a crude oil tanker that OFAC added to its sanctions list in January 2025 as part of efforts to crack down on Russia’s “shadow fleet.” As POLITICO reports, shadow fleet tankers are linked to deceptive ship-to-ship oil transfers, AIS manipulation (deliberate tampering with the Automatic Identification System on ships in order to hide or falsify vessel activity), and activity at sanctioned or occupied ports. Cerulean has linked multiple oil slicks to APUS over the past two years in Norwegian and Yemeni waters based on satellite imagery and vessel tracks.

Like Volgoneft-212 and Volgoneft-239, APUS is one of many such tankers that endanger ocean health and undermine sanctions integrity. By linking sanctioned vessels and oil pollution, Cerulean helps spotlight the risks posed by these vessels around the world, and will continue to expose their risks and help hold polluters and sanctions evaders accountable.