The data visualization accompanying the feature story “Some hungry fish are eating plastic—here’s why that matters” in the May 2019 issue of National Geographic shows observation data from microplastics studies around the world. Some values were published in peer-reviewed research, and other values were updated directly by experts in the field. Data from different studies may not be directly comparable because their collection methods varied. Conversions to “microplastic pieces per gallon of seawater or sediment” were made with expert oversight.
Seawater samples
North Pacific
0.047 pieces/L
Source: Laurent Lebreton, The Ocean Cleanup Foundation
Related Study: Evidence that the Great Pacific Garbage Patch is rapidly accumulating plastic
North Atlantic
105 pieces/m3
Source: Kara Lavender Law, Sea Education Association
Unpublished figure reported directly
Slicks off Hawaii
152.770 pieces/m3
Source: Jamison Gove and Jonathan Whitney, NOAA
Unpublished figure reported directly
Hangzhou Bay
990 pieces/m3
Source: Shiye Zhao, Harbor Branch Oceanographic Institute
Unpublished figure reported directly
Hope Island, Queen Charlotte Strait
9180 pieces/m3
Source: Peter Ross, Ocean Wise
Related Study: Widespread distribution of microplastics in subsurface seawater in the NE Pacific Ocean
Mariana Trench
13.51 pieces/L
Source: X. Peng and S. Chen, Chinese Academy of Sciences
Related Study: Microplastics contaminate the deepest part of the world’s ocean
Sediment samples
Polar Front
1 piece/25 cm3
Source: Colin Janssen, Ghent University
Related Study: Microplastic pollution in deep-sea sediments
Indian Ocean
4 pieces/50 mL
Source: Richard Thompson, University of Plymouth
Related study: The deep sea is a major sink for microplastic debris
Mediterranean Sea
35 pieces/50 mL
Source: Richard Thompson, University of Plymouth
Related study: The deep sea is a major sink for microplastic debris
Bay of Biscay
40 pieces/50 mL
Source: Richard Thompson, University of Plymouth
Related study: The deep sea is a major sink for microplastic debris
Mariana Trench
2,200 pieces/L
Source: X. Peng and S. Chen, Chinese Academy of Sciences
Related Study: Microplastics contaminate the deepest part of the world’s ocean
Fram Strait (HAUSGARTEN Observatory)
3,463 pieces/L
Source: Melanie Bergmann, Helmholtz Centre for Polar and Marine Research
Related Study: High quantities of microplastic in Arctic deep-sea sediments from the HAUSGARTEN Observatory
