Plastics Are Sailing the World's Oceans
Having attained almost every corner of the world, including the remote Arctic Ocean, plastic pollution has become one of the biggest environmental crises. Annual plastic production currently exceeds 280 Million tons, and it is expected to attain an alarming 33,000 Million tons by 2050 at current growth rates. Modern society depends on plastics and will increasingly so in the near future. Plastics are ubiquitous in the food system; e.g. food packaging, bottles, carrier bags, straws, single-use cutlery and plates, as well as discarded fishing gear and agricultural plastics.
The Vatcha Dam (Bulgary) covered with plastics.
Part of the plastics produced reach the oceans, mainly from mismanaged waste disposal on land, and amounts about 270,000 tons in the sea surface (Figure 1), and even more on the seafloor. Most plastics being made from petrochemicals, they will never fully degrade and it is said that all the plastic ever created still exists in some form (excluding plastic that has been burnt).
Figure 1 - Sea-surface plastic accumulates in the five subtropical gyres (Cózar et al. 2014).
Oceanic plastic causes a series of environmental problems. Marine wildlife, including seabirds, turtles and whales, can ingest plastics and suffer from damage or blockage of the digestive tract and starvation. Plastic consumption can disproportionately affect some groups within populations, e.g. the fitter, and threaten the populations' natural balance. Entanglement in plastic, and especially in discarded fishing nets ('ghost nets'), can also cause injuries and impair movement.
Plastics can also be toxic, they often contain polluting additives and can absorb contaminants from water and sediments. Gut acids can release the plastic contaminants, by which they enter the food chain, and can potentially bioaccumulate and attain humans. Furthermore, cosmetics and weathering of plastic debris release plastic pieces a few millimeters in size, called microplastics, which are consumed even by zooplankton, and are more efficient vectors of chemicals into bodies.
And finally, organisms like jellyfish and epibionts often colonize plastic debris that transport them to places where they may become invasive and threaten local biodiversity.
Plastics can also be toxic, they often contain polluting additives and can absorb contaminants from water and sediments. Gut acids can release the plastic contaminants, by which they enter the food chain, and can potentially bioaccumulate and attain humans. Furthermore, cosmetics and weathering of plastic debris release plastic pieces a few millimeters in size, called microplastics, which are consumed even by zooplankton, and are more efficient vectors of chemicals into bodies.
And finally, organisms like jellyfish and epibionts often colonize plastic debris that transport them to places where they may become invasive and threaten local biodiversity.
Summary of the life cycle of plastic.
Recycling and proper management of waste can reduce plastic pollution, but not all plastic can be recycled, and giving it an additional life doesn't ensure it won't eventually end up trashed too. Using biodegradable alternatives is another option, but it isn't flawless either, as it may not be designed to degrade in the cold ocean.
Reducing the use of plastic in the first place is the better solution, you can start by cutting down your own use of plastic.
Diego Garcia-Vega - December 24th 2017
Reducing the use of plastic in the first place is the better solution, you can start by cutting down your own use of plastic.
Diego Garcia-Vega - December 24th 2017