Researchers have made an alarming discovery about the widespread presence of plastic pollution across the North Pacific Ocean. An international team of scientists embarked on a five-week expedition aboard the research vessel Sonne in 2019 to investigate plastic accumulation in the ocean surface waters between Vancouver and Singapore.
The team utilized a predictive model from the University of Hawaii that calculated plastic loads to select nine sampling stations expected to have both high and low concentrations of plastic debris. In a surprising finding, samples collected from the Papahānaumokuākea Marine National Monument northwest of Hawaii contained equally large quantities of microplastics less than 5mm in size as locations predicted to have high plastic loads, such as the Great Pacific Garbage Patch. This remote protected area was not anticipated to have such substantial plastic accumulation according to the model’s calculations.
At each station, surface water samples were obtained using neuston nets with a fine 0.3mm mesh, allowing the collection of microparticles that evade larger-meshed devices. In the lab, researchers sorted and counted plastic particles by size, then used Fourier-transform infrared spectroscopy to chemically identify the polymers and assess their weathering state. As anticipated, the highest loads were measured near the central Pacific accumulation zone known as the Great Pacific Garbage Patch. However, plastics were detected in all samples across the expanse of the North Pacific surveyed.
A key finding was that more weathered and fragmented microplastics dominated farther offshore, supporting the hypothesis that smaller particles are transported over long distances as larger items disintegrate. But critically, even protected areas thought to be less affected contained concerningly high microplastic levels comparable to recognized hotspots. This pervasiveness suggests the problem impacts the entire ocean ecosystem rather than isolated regions. With marine life demonstrated to ingest microplastics, reducing emissions through policy and waste management improvements is vital to safeguard ocean health.
The researchers emphasize their data underscores the need for strong global cooperation to curb plastic pollution at the upcoming United Nations treaty negotiations. International action is urgently required to protect marine environments from the growing threat of pervasive microplastic contamination.
From Science Daily
The Trash Economy 