A man walks past sacks containing debris washed ashore from the X-Press Pearl on a beach in Colombo on Thursday. The plastic pellets will break down and be more difficult to clean up over time, marine biologist Asha de Vos says.

A man walks past sacks containing debris washed ashore from the X-Press Pearl on a beach in Colombo on Thursday. The plastic pellets will break down and be more difficult to clean up over time, marine biologist Asha de Vos says. / AFP via Getty Images

A sinking cargo ship off the coast of Sri Lanka is causing an environmental disaster for the country that looks set to have long-term effects.

The X-Press Pearl caught fire on May 20 and burned for two weeks, but the fire appears to have mostly burned out. The crew was evacuated. The ship is now partially sitting on the seabed with its front settling down slowly.

Its cargo is the concern: The ship was carrying dangerous chemicals, including 25 tons of nitric acid and 350 tons of fuel oil. The ship's operator says oil has not spilled so far. But what's already having an impact on beaches nearby are the 78 metric tons of plastic called nurdles — the raw material used to make most types of plastic products.

Wave after wave of plastic pellets are washing ashore. The ship is about 5 miles from the nearest beach.

"It's a beach that I've been to many times before," says marine biologist Asha de Vos. "It's that idyllic tropical beach with the palm trees and the beautiful sand."

De Vos visited the beach in the last few days. "It was just a beach covered in these white pellets," she tells All Things Considered. "This was after the Navy personnel had been cleaning for days on end. Every time they filled bags and took them inland amongst all these other thousands of bags, another wave would wash in with more pellets. So it just seemed so unending. To me, it was really sad to see."

Sacks containing debris washed ashore from the X-Press Pearl are pictured on a beach in Colombo on Thursday.

Sacks containing debris washed ashore from the X-Press Pearl are pictured on a beach in Colombo on Thursday. / AFP via Getty Images

De Vos says scientists don't fully understand the long-term effects of these plastics on animals. Here are excerpts of the interview, edited for length and clarity:

Marine life, of course, are eating these pellets. Is there a sense of the scale of the disaster?

I think right now we're really grateful that we haven't had an oil spill yet. And I think we're just really hopeful that that doesn't happen. But, you know, obviously, the immediate concern in the early days was the chemicals that were onboard. But the understanding is that they would have burned or if they fell into the water, spilled into the water, they could dissolve. So the impact of chemicals is mostly localized and short term.

But these plastic pellets, they're like these little buoyant microplastics that move around very easily with the currents and the wind and the waves. And we've found them all along the west coast, down the south coast now starting to move up the north coast. So, you know, it moves fast. It gets into all the nooks and crannies.

There are concerns about ingestion by species. That's more than likely going to happen. But the species that would be most affected would be the small fish, because that can block their pathways and stuff like that. Apart from that, larger fish would probably eject them.

But then there's also concern that these little particles, these pellets, can absorb chemical toxins from the ocean environment. And as they do so — and then they travel around, they obviously take these toxins with them. Now, this is obviously something that will be more of a concern down the line as they've been in the water for longer.

If an animal ingests that, we don't fully understand what can happen. And that's not just us. That is the global community that studies this.

A crab roams on a beach polluted with plastic pellets that washed ashore from the ship. Scientists don't know the full effects of animals ingesting these types of plastics.

A crab roams on a beach polluted with plastic pellets that washed ashore from the ship. Scientists don't know the full effects of animals ingesting these types of plastics. / AP

But also there are livelihood impacts. Fishermen can't go out to fish at the moment. These beaches are really quite important to our tourism industry. So far-reaching impacts for sure.

You describe these as microplastics. Are they the sort of thing that people can clean up or in some cases, are they just too small for that?

Microplastics that typically anything less than 5 millimeters. And so here, you know, they're still visible. You can clean them up, you can pick them up. Obviously, they're the same size of grains of sand. So that makes it a little bit tricky. The key thing right now is that in Sri Lanka, we are in a lockdown. So we can't deploy volunteers onto the beaches to go help clean.

Because South Asia is hard hit by the pandemic on top of this environmental disaster

Exactly. It's a fine balance between trying to maintain the health and safety of the people, but also at the same time try to manage this environmental disaster. But the thing is, right now, they're visible, right? Like that's where the shock is. When we see the photographs, you see these mounds of these plastic pellets.

But what will happen in time is that with the wind and wave action and UV radiation, these will start to break into smaller and smaller particles and they'll still be there, but they'll just be less visible. That's when it starts to become really difficult to clean them up.

Mano Sundaresan and Patrick Jarenwattananon produced and edited the audio interview. James Doubek produced for the web.

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