An extensive sheen detected in the waters west of Kharg Island - Iran's main oil hub - was likely caused by a tanker discharging contaminated ballast water, Iran's top environmental official said on Tuesday.
Satellite observations identified the suspected spill as a grey and white formation in the sea to the west of the 8-kilometre long island. Images from Copernicus Sentinel-1, Sentinel-2 and Sentinel-3 satellites captured the formation between May 6 and May 8, showing a slick spreading across dozens of square kilometres.
Iranian Vice-President Shina Ansari said monitoring results attributed the incident to the discharge of ballast water that had been contaminated with substances from a non-Iranian tanker. Ansari added that no oil leaks had been reported from pipelines or other oil facilities, according to state media.
Commenting on the imagery, Louis Goddard, co-founder of consultancy Data Desk, said the pictures likely showed an oil slick. He also noted the incident could represent the largest such event since the start of the U.S.-Israel war against Iran 70 days ago.
Key points
- Satellite imagery from Copernicus Sentinel-1, Sentinel-2 and Sentinel-3 captured a grey and white formation west of Kharg Island between May 6 and May 8.
- Iranian officials reported that monitoring indicates the slick resulted from ballast water discharge contaminated by a non-Iranian tanker, with no reported leaks from pipelines or oil facilities.
- An independent analyst described the images as likely showing an oil slick and said it could be the largest such incident since the conflict escalation noted as occurring 70 days ago.
Risks and uncertainties
- Attribution: While Iranian monitoring indicates a contaminated ballast discharge from a non-Iranian tanker, the available information does not provide additional corroborating evidence in the public record.
- Extent and impact: The slick was described as covering dozens of square kilometres in satellite imagery, but the article does not provide further details on environmental assessments or on-the-water verification.
The available reporting focuses on satellite observations and official statements. It does not include independent, on-site confirmation of the discharge or detailed environmental impact assessments. Further updates would be required to clarify the full scope of the incident.