It's no secret that plastic and other human trash are a problem for marine life, but our understanding has long focused on the ocean's surface. Now, a more complete picture is coming into focus, revealing that even some of our planet's greatest depths have become home to our debris. As described in a study published on September 16, 2026 in the open access journal PLOS One, an international team led by Dr. Daniel Lauretta of Argentina's natural science museum surveyed the Mar Del Plata Submarine Canyon in the southwestern Atlantic, finding that our trash has accumulated in a part of the planet we typically consider pristine.
The ocean's depths remain one of Earth's greatest unknowns, but as the fish swims—or as the debris sinks—the sea floor is not all that distant. On average, our oceans are just a few miles deep, and thus, not so far from human influence. This study, which took place in summer of 2025, marked the first time scientists had taken images of the seafloor within the Mar Del Plata Submarine Canyon. They documented approximately 40 species that may be new to science but also some more familiar sights.
Across 10 of the 17 dives with a remotely operated submersible, the researchers saw 29 identifiably manmade objects. The vast majority were plastic, along with a few rubber items. They ranged from fishing gear to plastic bags and food wrappers and even a boot. Some were buried in the sediment, while others were trapped in rocks or still drifting. The researchers observed more litter inside the canyon compared to the surrounding area, suggesting the geography and currents funneled these items into the fissure.
Researchers observed some animals also interacted with the waste. Mobile creatures like crustaceans had transient interactions while more stationary creatures—like starfish and corals—had attached to some debris, often partially subsumed plastic packaging and fishing ropes. Though life was present, the team cautioned that we can't assume these objects are suitable habitats.
This is not the only time scientists have found traces of our trash so far below the surface. Just a few months before the expeditions in the Mar Del Plata Submarine Canyon, a plastic bag was found in the Mariana Trench, the planet's deepest fissure. The sinking of organic material is essential to life beyond the reaches of sunlight, but this new study adds to emerging evidence that nutrients aren't the only matter pulled to the ocean floor.
The authors add: "Unveiling a species previously unknown to science in the endless darkness of the deep sea may be one of the most extraordinary experiences a marine biologist can have."
Author interview: https://plos.io/4ys71Nz
In your coverage, please use this URL to provide access to the freely available article in PLOS One: https://plos.io/3UwaXhS
Citation: Teso V, Urteaga D, Bozzano G, Bigatti G, Brogger MI, 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
Author countries: Argentina, Ecuador, USA.
Funding: The oceanographic expedition FKt250712 was funded by the Schmidt Ocean Institute (SOI), the Nippon Foundation-Nekton Ocean Census Programme ( https://oceancensus.org/) , CORDAP Coral Accelerator Program under Award No. CAP-2023–1502, and the AZARA Foundation. Funding was also provided by PICT 2020-1169 (Agencia I+D+I), PICT 2020-1215 (Agencia I+D+I), PIBAA 2022-0410 (CONICET), PIBAA 2022-0433 (CONICET), PIP 2022-0277 (CONICET), and Fundación ProyectoSub. All funders have no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
