One study showed that approximately a quarter of fish, sampled in locations in Asia and North America, had plastics and textiles debris in the digestive system[4]. Furthermore, young fish were shown to actively target plastics as a food source, affecting their physical performance and leading to an increase in juvenile deaths, which in turn decreases the breeding pool [5]. The concentration of the ingested toxins, therefore, increases up the food chain and in humans is thought to lead to some cancers, infertility, as well as immune, metabolic, cognitive and behavioural disorders.
Marine life, and specifically the feeding patterns of most marine animals, are centred around the location of phytoplankton. The major phytoplankton growth areas are along the coast, where nutrient rich water circulates back up after travelling along the sea floor, and is found up to depths of 100 metres, decreasing in concentration as the penetration of UV light decreases.
Plankton is defined as anything unable to swim against a current, where phytoplankton is a subtype of plankton. They can be considered analogous to plants as species of autotrophic photosynthesizers; the grass of the sea.
[1], [2] World Economic Forum, Ellen MacArthur Foundation and McKinsey & Company, The New Plastics Economy — Rethinking the future of plastics, 2016, (http://www.ellenmacarthurfoundation. org/publications).
[3] The New Economist, World’s worst marine polluters named and shamed, February 13th, 2015
[4] K. Gruber, New Scientist, Plastic in the food chain: Artificial debris found in fish, 25 September 2015
[5] Chelsea M. Rochman, Science, Ecologically relevant data are policy-relevant data, 03 Jun 2016