The Expert's Opinion
A Sea of Garbage
Kim Cornelius Detloff, NABU, 2012
Plastic debris poses a serious threat to the seas. According to estimates from the United Nations Environment Programme (UNEP), every year more than 6.4 million tons of waste ends up in the sea, 75 percent of it consisting of plastic. A major part comes from the land and reaches the sea through rivers, unfiltered drainage systems, or illegal garbage dumps. On average, 18,000 pieces of plastic now drift around on the surface of every square kilometer of water. The harmful detritus of our civilization is to be found in even the most remote seas. Cigarette filters, plastic bags, and plastic bottles head the list of the most frequently found items.
Hydrographic vortices in the ocean concentrate the waste material in enormous gyres of debris. According to recent estimates, the best known of these, the Great Pacific Garbage Patch in the North Pacific, has now reached the size of Central Europe. And what we see is actually just the tip of the iceberg. About 15 percent of the debris floats around on the surface, 70 percent collects on the seafloor, and a further 15 percent washes up onto the coastlines.
The impact of plastic on the marine environment is wide-ranging, and for sea creatures often dramatic. Dolphins and fish, for instance, get entangled in old nets and asphyxiate. Sea birds and turtles mistake plastic for their normal food, but they can neither digest it nor entirely excrete it. They starve to death with a full stomach or die from internal injuries. Today, at one of the world’s largest albatross breeding colonies on the Midway Islands in the Pacific, two of five fledglings die due to the effects of water pollution by plastic.
The lifespan of plastics in the sea can be up to 450 years, and only sunlight, salt water, and friction very slowly break down the material into smaller particles. Fish, mussels, or corals concentrate these microscopically small particles in their digestive systems or in their tissue. Often these creatures are severely polluted, as environmental toxins like the insecticide DDT (dichlodiphenyltrichlorethane) or PCBs (polychlorinated biphenyls) that dissolve in water collect on the surfaces of the plastic particles. In addition, the water-soluble toxic contents of plastic, plasticizers, or the notorious Bisphenol A damage animals’ genetic material as well as their hormone balance.
Alongside its ecological impact plastic waste also causes economic problems. Every year ports and local authorities must invest millions of euros in cleaning up beaches, while shipping, fishing, and industry are also confronted with high costs caused by damage to ship propellers, fishing gear, or filter systems.
Despite strict regulations, international shipping is one of the main avenues by which waste enters the sea—including the North Sea and the Baltic. What is known as the MARPOL (from Marine Pollution) Convention of the International Maritime Organization bans putting plastic into the sea, but often plastic is broken up with food waste in the ship’s own shredders and then illegally dumped. This allows the shipping companies and their captains to avoid the waste fees charged in the ports. The risk of being caught is minimal.
There is a European guideline intended to ensure that ports offer sufficient capacity for waste disposal. But its wording is not very concrete and has led to very different models of waste disposal in different ports. There are no standardized management plans, fee scales, or registration procedures, so shipowners are faced with differing charges and disposal procedures. But there are also a number of positive approaches, for instance those taken by the ports of Rotterdam or Malmö-Copenhagen. Their no-special-fee system covers the costs of waste disposal through the standard port charges without additional costs, thus eliminating the incentive to dispose of waste at sea.
Danger for Europe’s Seas
Garbage in the sea is a problem not just for distant stretches of coastline. In the North Sea, the Baltic, and in the Mediterranean littering is advancing inexorably. Every year an estimated 20,000 tons of waste enter the North Sea alone. If towns and communities were not to clean our holiday beaches at considerable expense, a seaside holiday on Sylt or Fehmarn would be a rather grimy affair. In 2009, the regional Convention for the Protection of the Marine Environment of the North-East Atlantic (OSPAR) counted, on average, 712 pieces of waste per 100 meters of coastline, three quarters of it consisting of plastic. So far extensive studies for the Baltic are lacking, but not all regions appear to be affected to an equal extent. According to figures from the Helsinki Commission (HELCOM), up to 60 percent of the garbage originally comes from tourism.
The Mediterranean is also seriously affected. In January 2011 scientists of the French Ifremer institute estimated that more than 250 billion pieces of plastic drift around in the upper ten to fifteen centimeters of the water column alone. The main sources are tourism, poorly filtered wastewater, shipping, and illegal dumping.
The Need to Take Action
Although our knowledge about the dangerous consequences of plastic garbage is still incomplete, there is a clear need for immediate action. Only if society as a whole determinedly accepts the challenge can we win the battle against the use of the sea as a garbage dump and secure our oceans’ future.
Dr. Kim Cornelius Detloff is a marine biologist and works as consultant for marine protection at NABU, the Nature and Biodiversity Conservation Union Germany. After studying at the University of Hamburg, he spent a number of years as a scientist and private lecturer at the Institut für Marine Biologie on the Italian island of Giglio. From 2006 to 2008 he was employed as a campaigner by the International Fund for Animal Welfare (IFAW). After a year as political-scientific advisor to the Bonn Convention (CMS), he today works at the NABU headquarters in Berlin.