The Problem

Defining the Problem

There has been extensive media coverage about the "garbage patch" over the past several years, and not all of it has been verifiable or accurate. Some have called it the Great Pacific Garbage Patch, Plastic Island, Trash Island, the Plastic Vortex, and the North Pacific Gyre. In truth, a "gyre" is simply a large-scale circular feature made up of ocean currents that spiral around a central point creating a whirlpool effect that pushes water and marine plastic debris to its center. As plastic enters the marine environment, currents like the Kuroshio off the coast of Japan, collect and transport it like a giant ocean conveyor belt laden with garbage bound for the North Pacific Gyre.

Worldwide, there are five major subtropical oceanic gyres: the North and South Pacific Subtropical Gyres, the North and South Atlantic Subtropical Gyres, and the Indian Ocean Subtropical Gyre. Because more data has been collected in the North Pacific Subtropical Gyre, we are gaining a better understanding of the scope of the marine plastics issue and its impact on the environment. But as scientific research continues in the four other major oceanic gyres, it seems reasonable to predict that similar amounts of plastic will be found in those gyres a well.

Estimates vary widely as to the size of the North Pacific Gyre - some research suggests that there are literally millions of tons of marine plastic debris distributed over 5 million square miles of ocean - but regardless of the exact size and mass of the garbage patch, one thing is clear; plastic garbage does not belong in our oceans.

Most plastics in use today, excluding the few plant-based alternatives slowly reaching the market, are made of petroleum, and as a result they float like oil on or near the surface of the ocean. When exposed to sunlight over prolonged periods of time, these plastics break up into smaller and smaller particles until all that remains is a fine plastic dust. Unfortunately, this seemingly harmless plastic dust retains all its chemical components and will never biodegrade. In fact, unless it was incinerated, all of the plastic ever made remains in the environment to this day.

Sources of the Debris

It has been reported in the press that 20% of marine plastic debris ends up in the ocean as a result of maritime industries (cruise ships, commercial fishing, oil platforms, the shipping industry), with the remaining 80% originating on land. While the source of this statistic may have been an extrapolation of data gathered over the years during world-wide coastal cleanup efforts, exact percentages may never be verifiable. But whatever the source, the truth of the matter is WE put it there, now WE need to clean it up.

What we do know for certain, however, is that polluted waterways are a major source of marine plastic debris found in the world's oceans. After a heavy rain, coastal rivers and streams carry many different pollutants to the sea. As rainwater washes into gutters and storm drains, it carries with it all that we humans have carelessly left behind. In addition to the mountains of discarded trash that make their way to the gyre every year, there is an equally dangerous cocktail of hazardous chemicals spilling into our oceans; gasoline, motor oil, and anti-freeze from our cars, pesticides and fertilizers from agricultural operations, vast amounts of manure from stockyards and animal processing plants, and even human waste and pharmaceutical residue from faulty septic systems and overloaded sewage treatment plants.

Among the many chemical and biological toxins found floating in the ocean, scientists have identified a number of particularly harmful compounds called "persistent organic pollutants" or POPs, and exposure to them can cause death and illnesses including disruption of the endocrine, reproductive, and immune systems. The United Nations Environment Programme Governing Council refers to these contaminants as the "dirty dozen"; chemicals like DDT and DDE which were commonly found in pesticides, PCBs which are used in automobile fluids and flame retardants, and dioxins (found in herbicides and as a byproduct of waste incinerators).

Researchers are now learning that floating plastic particles attract POPs from surrounding sea water like a magnet, and as these plastic particles make their way through the oceanic currents, they accumulate and transport them around the globe. Many of these pollutants are known carcinogens and are potentially harmful to both animals and humans when ingested. Studies have also shown that these plastic particles contain POP levels up to a million times higher than in surrounding sea water.

Entanglement

Derelict fishing equipment like drift nets, long lines and other abandoned fishing gear can also be found in abundance in the world's oceans. This equipment was designed to catch and kill fish for human consumption, but when abandoned, it presents a lethal obstacle for any marine animal that happens to encounter it. These floating mounds of nylon rope, buoys, and monofilament line, sometimes referred to as "ghost nets", can stretch for miles and weigh up to several tons. In addition to posing a serious navigational hazard to commercial and private sailing vessels, animals like albatross, turtles, seals, and even dolphins and whales face certain death when they become entangled in it.

Plastic and Toxins in the Food Web

As floating plastic breaks up into ever-smaller pieces, it begins to make its way into the oceanic food web. Many animals mistake these small, colorful pieces of plastic for food and ingest them, and though it has not been proven yet, these plastic particles may also be releasing harmful contaminants into the animals that eat them. If the plastic cannot pass through the animal's digestive system, it fills their stomachs with garbage that has no nutritional value, and with no room for its natural food, animals like sea turtles and birds will slowly starve to death.

Implications for Humanity

As plastic builds up in the food chain carrying with it increasing amounts of toxins, there is the potential that it could reach food organisms that are harvested by humans. We are the apex predator of the sea and when we consume fish and seafood, we consume everything that they have consumed. There is growing evidence that some of the toxins associated with plastic particles in the gyre are responsible for an increase in health problems in humans such as endocrine cancers and brain damage, as well as reproductive and cardiovascular damage.