Scientists Sent a Robot 3 Miles Below the Ocean—What It Found Is a Warning - Newsweek

Hundreds of miles from shore and thousands of feet below the ocean's surface, scientists have uncovered remarkable evidence highlighting the extent of the human footprint.

A team of researchers exploring the Mar del Plata Submarine Canyon off the coast of Argentina discovered marine litter scattered across the deep-sea floor, showing that even some of the most remote environments are not immune to pollution.

The findings, published by non-profit organization PLOS One, were based on surveys conducted using a remotely operated vehicle (ROV) capable of descending to depths of 4,500 meters—nearly three miles beneath the surface. Debris found on the seafloor was mapped and then categorized into individual pieces of litter from plastic sheets, bags, food wrappers, and fishing gear.

Lead researcher Daniel Lauretta of Argentina's Museo Argentino de Ciencias Naturales and the Deep Sea Studies Group of Argentina (GEMPA) told Newsweek that the results highlight that "even very remote and deep environments are not completely isolated from human activities."

"The deep sea may appear remote and disconnected from our daily lives, but it is still connected to activities occurring at the ocean surface," he said.

Co-author Diego Urteaga went on to note that the litter they found was more consistent with “waste generated by vessels operating offshore,” such as fishing vessels.

"The most surprising thing is that objects associated with our everyday activities can be found at such depths," Urteaga told Newsweek. "When you are looking at the seafloor nearly two miles below the surface, it is easy to imagine a world completely separated from human activity. Then you suddenly encounter a piece of fishing gear or another manufactured object."

Submarine canyons are vast underwater valleys carved into the continental shelf. Scientists consider them to be hotspots for biodiversity because they can support an abundance of marine life.

The Mar del Plata Submarine Canyon lies roughly 186 miles from the Argentine coastline. However, researchers noted that ocean currents can transport waste over vast distances, meaning some items may have traveled quite some distance before reaching the canyon.

Urteaga said the most memorable moment came when a fishing rope suddenly emerged in front of the ROV, forcing operators to act in order to avoid a collision.

As for Lauretta, the “most striking” find was a solitary boot resting on the seafloor. Nonetheless, what surprised Lauretta the most was the relatively low quantity of litter they discovered.

"The relatively low amount of litter we observed compared with some other submarine canyons is certainly an important finding. However, we would be cautious about interpreting it simply as evidence that the canyon is unaffected or that there is no reason for concern," Lauretta said.

It is vital to consider the geographical characteristics of the Mar del Plata Submarine Canyon though. Despite its relatively remote location, human debris still made its way to the depths of the canyon.

Speaking to Newsweek about the findings, Sian Sutherland, co-founder of A Plastic Planet, said it is "proof that there is no 'away’ when it comes to plastic." Her organization works with governments and businesses to offer sustainable alternatives to plastic in order to cut down on pollution.

“Plastic is designed to last. It can be carried vast distances by rivers and ocean currents before sinking, becoming trapped in underwater canyons and remaining there for decades or longer. What we discard for a few minutes can become part of an ecosystem for generations." Sutherland said.

The study also found evidence that marine organisms were attaching themselves to discarded objects, which scientists warn could transform rubbish into artificial habitats, potentially changing deep-sea ecosystems.

While the amount of litter observed was lower than many submarine canyons elsewhere in the world, the researchers hope the findings serve as a reminder that pollution can reach even the most isolated corners of the ocean.

"We are still discovering how these deep-sea ecosystems function and how many species live there, yet traces of our activities are already reaching these environments," Urteaga told Newsweek. "The deep ocean is not an empty or distant space. It is a living environment, and our actions at the surface can reach places that seem unimaginably far away."

What the canyon could look like in years to come remains unknown, but the importance of preventing litter from entering our oceans should not be underestimated. Lauretta and Urteaga believe preventative methods are far more effective than trying to remove litter once it has already made its way to the seafloor.

As this study offers a snapshot of the underwater conditions, they note that repeated observations of deep-sea areas are essential to recognize changes and distribution of litter. They plan to expand similar surveys to other deep-sea canyons around Argentina to better understand the scale of pollution in the region and establish a baseline for future monitoring.

Teso, V., Urteaga, D., Bozzano, G., Bigatti, G., Brogger, M. I., Brusa, F., et al. (2026). Out of sight, hidden into the deep: Marine litter in the Mar del Plata Submarine Canyon (southwestern Atlantic) revealed by ROV survey. PLOS One, 21(9), e0357098. https://doi.org/10.1371/journal.pone.0357098