10/10/2026
Out of sight is not gone.
Abandoned oil and gas pipelines are still shedding plastic into the ocean: decades after decommissioning.
A new study led by researchers at the University of Plymouth estimates that degrading pipelines and umbilicals on the UK continental shelf could generate up to approximately 500 metric tons of microplastics each year. Up to 121,000 metric tons of plastic may remain on the North Sea floor.
Researchers examined real pipeline samples left on the seafloor for 22 years. Scanning electron microscopy revealed cracks and fragmentation caused by long-term abrasion from sand, currents, and marine life.
The issue extends beyond the North Sea: an estimated 55% of the UK inventory may never be recovered, while more than 97% of pipelines decommissioned in the USA since the 1960s have reportedly been left on the seafloor.
“Decommissioned” does not mean gone. Plastic left behind can continue breaking down: and entering marine food webs.
Source: Journal of Hazardous Materials, DOI 10.1016/j.jhazmat.2026.143055; ScienceAlert, August 30, 2026.