- Experts and environmental officials brace for the worst as the partially sunk cargo ship MV X-Press Pearl threatens a massive oil and chemical leak, in addition to the millions of plastic beads it has already released.
- The pearls, or nurdles, have been the most significant manifestation of the disaster so far and have washed up along the island’s west coast around Colombo, with indications of underwater plastic pollution as well.
- The ship’s nitric acid cargo and bunker fuel pose threats of widespread pollution and changes in seawater chemistry, which could cause serious damage to sensitive marine ecosystems.
- In the long term, the build-up of microplastics along with diluted chemicals could spread through the food web and contaminate entire ecosystems for years or even decades to come, experts warn.
COLOMBO – Along the coastline north of Colombo, Sri Lanka’s commercial capital, the beaches are littered with millions of tiny white dumplings, each the size of a peppercorn.
“Polyethylene pellets can be seen everywhere along the beaches,” says Mala Damayanthi Amarasinghe, a senior professor at the University of Kelaniya.
They are also in the water, and anecdotal accounts paint a disturbing picture of their extent there. Local fishermen set nets in their traditional fishing grounds and returned a few days later, Amarasinghe tells Mongabay. “They discovered that there were no fish and that the nets were covered with synthetic fibers which made them completely unusable,” she says. “This indicates that the bottom of the fishing area contains material from the burning vessel.”
The “burning ship” is, or was, the MV X-Press Pearl, a newly built Singapore-flagged freighter that caught fire in late May and partially sank off Colombo in early June. The ship’s cargo, much of which fell overboard during the fire and subsequent sinking, included several containers of plastic balls, or nurdle – the raw material for the manufacture of plastic articles – as well as 25 tons of nitric acid. It also carried 378 tonnes of bunker fuel.
So far, the most visible impact of this marine disaster has been the millions of nurdles that washed up on the shore, got caught up in the mangroves or remained in the sea.
“Debris and microplastics can cause entanglements, infections, injuries and higher death rates in marine life,” says Dilanthi Koralagama, a lecturer at the University of Ruhuna. “Seabirds could ingest the plastic pellets or debris, which would negatively affect their health or even kill them. “
But there are also growing concerns about the potential leaks of nitric acid and bunker fuel, which would exacerbate what is already described as one of Sri Lanka’s worst environmental disasters. It was a nitric acid leak that fueled the fire aboard the ship in the first place.
Amarasinghe says that in some places patches of vegetation along the water appear to have suffered burns and died, possibly from chemicals sweeping the shore with the waves. Apart from this, there is no visible damage to the coastal environment and surface waters, and the mangrove ecosystems and lagoons do not appear to be affected so far.
Prepare for the worst
Water samples have been taken for analysis and the situation is being closely monitored, but at this point there are only scenarios, possibilities and contingency plans, according to experts and officials. Much will depend on the exact chemical makeup of any chemical disclosed, its dilution in the ocean, as well as currents and weather conditions.
“These chemicals can be diluted in water, but we don’t know how far they can travel,” says Sudarsha De Silva, co-founder of the Earthlanka Youth Network. “If the dilution continues and the contamination reaches a large area, it could affect coral reefs and other marine ecosystems. However, due to its high buffering capacity, it is very difficult to achieve pH value changes in seawater.
Changes in seawater chemistry could affect mangroves and seagrass habitats, according to DDGL Dahanayaka, aslecturer at the Open University of Sri Lanka. “Coral reefs are particularly sensitive to prolonged increases in seawater temperature and changes in pH. In the current scenario, nitric acid leaks can cause temperature increases and pH changes in the area, increasing the chances of coral bleaching and death.
Hemantha Withanage, executive director of the Colombo-based NGO, the Center for Environmental Justice, said the X-Press Pearl was carrying other potentially dangerous cargoes. “Besides chemicals, there is copper slag, lead ingots and other substances harmful to the environment. Until they are completely removed from the ocean, they will continue to cause damage. We do not know how many months it will take to remove them, as it is a difficult task and must be done by specialist divers.
The area around which the X-Press Pearl now sits half-submerged, about 16 kilometers (10 miles) offshore, includes fertile fishing grounds and is the habitat of a rich biodiversity including many species of fish. , crabs and shrimps. “Generally, the continental shelf area has the highest biodiversity of the entire marine environment,” Koralagama said. “The accumulation of contaminants and harmful substances could be fatal for this biodiversity.
The coastal and marine environment is complex and highly interconnected, she adds. Beyond the direct impacts, there is a strong possibility that contamination could spread through food webs and affect plants, animals and, ultimately, humans.
Koralagama notes, for example, that deposits of microplastics on algae and zooplankton reduce the release of oxygen through photosynthesis and cause higher mortality and contamination among the small pelagic species that feed on them. If seagrass beds and coral reefs are affected, fish and shrimp will lose their breeding grounds and habitats. Changes in water quality or temperature can also affect fry or destroy fish eggs, larvae and plankton.
“The long-term accumulation of debris, hydrocarbons, microplastics and other harmful substances in coastal waters, lagoons and estuaries could cause gradual changes, spreading to other peripheral areas towards Kalpitiya and Mannar”, Koralagama said. “A loss of primary producers and fry could make the entire ecosystem unhealthy and unsustainable. “
Sometimes the impacts are only visible after a long time. Amarasinghe cites the case of the mangroves in the Koggala Lagoon which began to produce strange discolored propagules – seed pods – which could alter their reproductive cycle. She says the cause of this could be a major oil spill that happened 15 years earlier, in 2006.
The potential short-term and long-term environmental impacts are serious, but there are options and plans to mitigate them. Already, oil dams have been installed across the lagoons, fishing activity has been restricted and clean-up efforts are underway with the participation of the Marine Environment Protection Authority (MEPA), Coast Guard, Navy, Air Force and other government agencies.
“MEPA has set up an operations room to manage the situation and coordinate efforts,” explains Terney Pradeep Kumara, MEPA’s director general. “We wait for the waste to arrive on the coast and use all the processes to collect it. In a next step, the waste will be sorted and recycled or eliminated. However, there is 60-70% of the sand collected with the nurdles which must be mined and transported to the shore. “
Koralagama says the technology exists to safely remove oil and other harmful substances from the sunken ship. She adds that frequent water quality testing, long-term monitoring, and the application of buffer methods to absorb contaminants are needed to better understand and mitigate the impacts.
Despite concerted efforts, it may not be possible to mitigate all impacts, says Withanage: “Plastic pellets cannot be completely removed from the environment, they will stay there for hundreds of years. Anything that leaked from the destroyed ship could remain in the environment and impact food webs through bioaccumulation, he says. “Even five to ten years later, we will find contaminated fish. The chemical contamination could be there for the next two decades, and the fish that feed in the area will continue to be contaminated. “
At this time, the true magnitude of the impact on Sri Lanka’s marine and coastal environment is uncertain. Even with mitigation and protection measures in place, the X-Press Pearl incident has the potential to seriously affect biodiversity and ecosystem services, threatening natural systems as well as livelihoods, well-being. and the coastal economy.
Banner image of plastic pellets, or nurdles, lining the west coast of Sri Lanka, courtesy of the Pearl Protectors.