An estimated 8 million tonnes of plastic enter the ocean every year. Five major oceanic gyres concentrate floating debris into enormous "garbage patches," the largest of which — the Great Pacific Garbage Patch — covers an area roughly three times the size of France. Microplastics, fragments smaller than 5mm, have been found in every ocean environment tested, from Arctic ice to the deepest trenches. Marine organisms at all trophic levels ingest microplastics, with documented impacts including reduced feeding, growth inhibition, and reproductive impairment.