Table 2 Ratios of surface plastic load to local pollution sources in the Arctic and other ocean basins.
Land-based pollution sources (L) were estimated from a population in a 50-km coastal strip, and sea-based pollution sources (S) were estimated from at-sea vessel density. Surface plastic loads (P) were obtained from the present work and previous reports (2, 7). L and S are expressed in persons or vessels per square kilometer of ice-free waters, respectively. S:L ratios are expressed in vessels per person, P:L ratios are expressed in grams of plastic per person, and P:S ratios are expressed in grams of plastic per vessel. Global estimates do not include the Southern Ocean because of the lack of plastic pollution data for that basin.