What’s really happening beneath the Ocean surface?

When you hear of plastic ocean pollution, you may only think of images of floating waste like The Great Pacific Garbage Patch (litter that has ended up spinning on the surface of the North Pacific Ocean) — a large and visible reminder of the scale of plastic pollution in our oceans. 

However, what’s less discussed is what’s actually happening beneath the surface. What does plastic ocean pollution do to marine life that is less visible? 

It affects marine life in many ways. Plastic ingestion by sea life not only has immediate negative effects, but also long-term flow-on effects to other species and marine ecosystems, including humans. Biomagnification (or bioaccumulation) is one example of this and refers to when contaminants or toxins build up in predators faster than they can be broken down.

Animals higher on the food chain will eat a higher volume of their prey, resulting in a higher volume of toxins in their body. As humans are at the top of this food web, this means we are consuming the largest concentration of microplastics out of any species. A new study found microplastics in 99% of seafood samples, with the highest levels in shrimp, showing just how polluted our seafood is with microplastics. 

Subscribe to our fortnightly newsletter

Get our top stories straight to your inbox every two weeks and stay informed about plastic pollution!

        SUBSCRIBE

Plastic ocean pollution also has detrimental effects to marine habitats, with coral reefs being a clear example of this. Plastic debris in the ocean can smother coral, blocking the sunlight needed for coral to thrive and exposing it to harmful toxins that compromise coral health.

Alongside this, chemical pollution (when the ocean is contaminated with chemicals not found there naturally), also occurs directly and indirectly from industrial or agricultural run-off, landfill, urban sewage and wastewater, or oil spills and leaks, and impacts the survival of individual species and the balance of populations of sea life interacting in an environment.

From food chains injected with plastic pollution to ruined habitats, what happens to marine life below the surface matters - not only because it directly impacts the humans above it, but because it directly impacts everything above it. 

"Living for nearly a hundred years on this planet, I now understand the most important place on Earth is not on land, but at sea,” Sir David Attenborough said in his 2025 documentary Ocean with David Attenborough. “For if we save the sea, we save our world."

+++++++++++++++++

For more information contact: info@scarabtrust.org.uk

Images:

floating plastic bag - Photo by Naja Bertolt Jensen on Unsplash (ST ref:1392)

Galapagos shark entangled with a closure ring for plastic drums - Image by Naiti Morales (ST ref: 1393)

Plastic on corals, pockets - Image by q phia (ST ref:1394)