Marine Litter Vital Graphics

DEFINITIONS

Mostly plastic

Composition of items collected

Other Plastic, higher estimate Plastic, lower estimate

Percentage

100

90

80

70

Average

60

Between 60 and 90 per cent – sometimes as much as 100 per cent – of the litter that accumulates on shorelines, the sea surface and the sea floor ismade up of one or a combination of different plastic polymers. The most common items, constituting over 80 per cent of the litter stranded on beaches (Andrady, 2015) are cigarette butts, bags, remains of fishing gear, and food and beverage containers. Likewise, 90 per cent of the litter collected from sea floor trawls is made up of plastic (Derraik, 2002 and Galgani et al., 2015). Plastics have only been mass-produced for around 60 years and therefore it is impossible to know with certainty how long they last in the marine environment. Most types of plastic are not biodegradable (Andrady 1994). In fact, they are extremely durable. This means the majority of polymers manufactured today will persist for decades and probably for centuries, if not millennia. So-called degradable plastics may persist for a long time because their degradation depends on physical factors, such as exposure to light, oxygen and temperature (Swift & Wiles 2004). Biodegradable plastics also decompose through the mediation of certain micro-organisms. Plastics labelled as biodegradable, designed to undergo certain degrees of degradation in landfills or in terrestrial environments, may still persist for long periods under marine conditions (Kyrikou & Briassoulis, 2007; UNEP, 2015). Full degradation of a plastic item implies complete breakdown and decomposition into water, carbon dioxide, methane and other non- synthetic molecules. For the large majority of plastic items, even if they disintegrate by breaking down into smaller and smaller plastic debris under the influence of weathering, the polymer itself may not necessarily fully degrade into natural chemical compounds or chemical elements under marine conditions (Hopewell et al., 2009).

50

40

30

20

10

1

5

10

15

20

25

30

35 37

Collection sites

29

32

26 17

33

22

1

6

418

30

14

21

15

12

2

9

23

31

36

28

25

13

34

37

Sea oor Surface water Beach, shoreline

11

3

27

19

24

16

8

10

20

7

35

5

1. Bay of Biscay 2. North Atlantic harbours (4 sites) 3. South African beaches (50 sites) 4. Cape Cod 5. Sub-Antarctic Islands (9 sites)

20. Macquire Island 21. French Mediterranean Coast (avg.) 22. European coast (avg.) 23. Mediterranean Sea 24. Tasmania (88 sites) 25. Curaçao 26. South Wales 27. South Australia 28. Mexico 29. International Coastal Cleanups, 1992 (avg.) 30. Tokyo Bay 31. Georgia 32. Kodiak Island 33. Halifax Harbour 34. St. Lucia 35. Heard Island 36. Dominica 37. Fog Bay, Northern Australia

6. National Parks in USA 7. Prince Edward Island 8. Bird Island 9. North Paci c Ocean 10. Gough Island 11. Transkei, South Africa

12. Gulfs in W. Greece (2 sites) 13. Caribbean coast of Panama 14. Mediterranean beaches (5 sites) 15. NW Mediterranean sea bed (avg.) 16. New Zealand Beach 17. South German Bight 18. Island Beach State Park, New Jersey 19. Argentina

Source: Derraik, J., G., B.,The pollution of the marine environment by plastic debris: a review, 2002

Marine Litter Vital Graphics

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