BBC uncovers lasting toxic legacy of cargo ship disaster off Sri Lanka

In November 2024, the BBC and Watershed Investigations sent more than 20 of those samples to a team of forensic chemists specialising in environmental pollution from Manchester Metropolitan University.

They found the most heavily contaminated nurdles were those burnt in the fire, which leach metals toxic to aquatic life, like arsenic, lead, cadmium, copper, cobalt and nickel.

The team also found the pellets "still going round appear to be sucking up more pollution from the environment" and were becoming "more toxic", according to Mr Megson.

"They will be ingested [and] will pass pollution on to marine organisms," he says.

Tests carried out on fish caught near the site of the disaster - as well as the nearby Negombo lagoon - found some contained the same pollutants that were present in the ship's cargo and on the nurdles.

Some of the fish contained levels of hazardous metals - some of which were found in the disaster - which exceeded safe limits.

Researchers say the disaster cannot be discounted as the source of contamination, although it also can't be directly proven to be the source, as it's not known if these fish ate nurdles, how many they ingested, or if the pollution came from other sources.

"But placed on top of everything else that is in that system, there's a really good likelihood that it's causing harm to the environment and also potentially harm to people and humans that are eating and relying on that marine ecosystem for a source of their food," Mr Megson adds.

Local fishermen do draw the link to the disaster.

"There's no fish since then. We've never had the same amount of fish that we used to catch," fisherman Jude Sulanta explains.

"Our lives have turned upside down. From the stretch where the ship sank up until here you don't get many new, young fish at all."

The ship's owner, X-Press Feeders Ltd, says to date it has worked diligently to ensure the best response to the disaster and spent more than $130m (£96m) to remove the wreck and debris at sea.

It says it has also paid more than $20m to the Sri Lankan government for clean-up operations on the coast and to compensate fishermen.

It says, however, that the Sri Lankan government has assumed responsibility for all shoreside clean-up activities and it is disappointed by the delays in that process and the ongoing impacts this is having.

The Sri Lankan government says the amount paid by the ship's owner - which was capped by an interim UK maritime court order - is not enough to cover the long-term damage, and it is pursuing legal action to overturn the cap and secure further compensation.

On Thursday, Sri Lanka's Supreme Court ordered the company to pay $1bn as an initial payment to cover long-term economic and environmental damage it says the country suffered as a result of the disaster - but the cap remains in place. The Supreme Court doesn't have jurisdiction over Singapore, where X-Press Feeders Ltd has its headquarters.

X-Press Feeders said it was extremely disappointed with the judgment and that they are reviewing it with their legal advisers, insurers and other relevant stakeholders to best assess their next course of action.

Prof Prashanthi Guneeardena - an environmental economist at University of Sri Jayawardenapura who chaired an expert committee of scientists to assess the damage - puts the cost of the disaster at closer to more than $6bn, taking into account things like the loss of wildlife, as well as impact on tourism, fishing and harm to local residents from the toxic cloud released when the ship burned.

"Large quantities of dioxin and furan have been added to the atmosphere and these are carcinogens. And then we have calculated it may kill about 70 people in our country," says Prof Guneeardena.

The ship owner rejects this assessment.

It quotes the International Tanker Owners Pollution Federation (ITOPF), an organisation which is funded by the shipping industry to assess marine spills. It says the report was "unparticularised, inaccurate, and lacked credible scientific basis".

The ship owner has also said itself and its crew have "followed the internationally accepted procedures in dealing with the acid leak, while maintaining all safety and emergency protocols".

Colombo Port Authority has also denied any responsibility, saying it did not know of the issues until the ship arrived in its waters.