Around the world, plastic pollution has become a growing problem, clogging our waterways, damaging marine ecosystems, and entering the marine food web. Much of the plastic trash we generate on land flows into our oceans through storm drains and watersheds. In 2005 the United Nations Environmental Program reported that there are 46,000 pieces of visible plastic floating in every square mile of the ocean, constituting approximatley 90% of all trash floating on the ocean’s surface. Plastic can be found in all of the major oceans and along beaches throughout the world.
Our oceans are dynamic systems, made up of complex networks of currents that circulate water around the world. Large systems of these currents, coupled with wind and the earth’s rotation, create “gyres”, massive, slow rotating whirlpools in which plastic trash can accumulate. The North Pacific Gyre, the most heavily researched for plastic pollution, spans an area roughly twice the size of the United States - though it is a fluid system, shifting seasonally in size and shape. Designed to last, plastic trash in the gyre will remain for decades or longer, being pushed gently in a slow, clockwise spiral towards the center. Most of the research on plastic trash circulating in oceanic gyres has focused on the North Pacific, but there are 5 major oceanic gyres worldwide, with several smaller gyres in Alaska and Antarctica.
Plastic poses a significant threat to the health of sea creatures, both big and small. Over 100,000 marine mammals and one million seabirds die each year from ingesting or becoming entangled in plastic. Plastic is also unusually toxic once it enters the ocean environment. Plastic particles are magnets for different types of pollutants, such as DDT (dichlorodiphenyltrichloroethane) and POPs (Persistent Organic Pollutants), and expel harmful chemicals such as BPA (Bisphenol A). Organisms at the bottom of the food chain, such as plankton and krill, ingest the chemicals along with the microscopic plastic particles. As larger fish consume the smaller ones, the chemicals work their way up the food chain. Ultimately, people consume the largest fish, having a devastating effect on human health.
It takes 500-1000 years for plastic to degrade. Even if we stopped using plastics today, they will remain with us for many generations, threatening both human and ocean health. Despite these alarming facts, there are actions we can take to address the problem of plastics.
Sources: plasticoceans.net; savemyoceans.com; cleanoceanaction.org; and 5gyres.org