The ocean has a large current system. Within these currents, there are 5 major gyres which are large eddy-like features. Within the gyres is where the ocean circulates and thus the trash congregates. The plastic here is stratified within the first 25 feet of the water column. Scientists with the Algalita Marine Research Foundation have studied plastics in the North Pacific Gyre for the past 20 years. They have found that plastic pieces, including tiny microscopic bits of plastic, have accumulated in the gyre forming a thin soup. It is estimated that about 80% of the material found in the gyre comes from land via stormwater runoff, while the remaining 20% appears to be from marine sources like fishing or shipping.
Microplastics are small bits of plastic that are found in our oceans, sound, lakes, and creeks. A microplastic is defined as any piece of plastic smaller than 5mm wide (roughly the width of a pencil eraser). There are two kinds of microplastics:
Microplastics have the same chemical structure as the larger plastic items from which they originated but are small enough to be ingested at every level of the food chain from plankton to whales. Since ocean plastics absorb toxins as well as leach toxic additives, microplastics can act like poison pills to the sea life that ingest them. Many plastic additives are endocrine disruptors that change hormone levels affecting behavior, development, and reproductive health.
Disposable one-use plastic products like bags, take-home containers, and bottles are used for a few minutes but last from 15-1000 years in the environment. Generally, plastics don’t decompose but instead photodegrade into smaller and smaller bits. Out in the ocean, they break down into “microplastic” bits that can be as small as or smaller than plankton.
Those thin plastic grocery bags have an average useful life of 12 minutes and then end up in the landfill, as litter or wrongfully placed in the recycling bin. Littered bags clog storm drains and can end up being eaten by wildlife or entangling animals. As the bags shred from exposure to the elements, they break up into smaller particles called microplastics. The microplastics can easily transmit to the rivers, creeks, streams, and Puget Sound affecting the native organisms that call those places home. Paper bags are recyclable, but they have a carbon footprint from production and transportation. The best way to eliminate unnecessary waste is to bring your own reusable bags to the store. And they’re easier to carry when full of groceries.
Placing plastic bags in the recycling causes contamination to the recyclable bails and the recycling facilities. Within the recycling facilities the bags get caught in the sorting machinery, when this happens the bags get stuck flat between the paper and will contaminate the paper bail. WA Dept. of Ecology estimates that plastic bags cost recyclers $700 to $1000 per ton of recycled material.
Paper bags are recyclable, compostable, and decompose readily in the environment, but they are not a perfect alternative. Paper bags are heavier than plastic bags and therefore require more fuel to transport from the point of production to the retailer. It helps that paper bags are required to be made of at least 40% post-consumer recycled content and that paper bags are 100% recyclable and compostable. A recycled content paper bag can become a paper bag again unlike a plastic bag which even if recycled will be degraded into a lower-quality plastic and used in a composite material like deck material instead of becoming a plastic bag again. The other important thing to note about paper bags is that paper comes from a renewable resource, trees, whereas plastic bags are made from nonrenewable fossil fuels. Ideally, everyone would bring their own reusable bags instead of using paper bags which is part of why there is a fee for paper bags.
Less than 5% of plastic bags and other non-durable plastics are recycled. Some grocery stores participate in WRAP, the Wrap Recycling Action Program, which collects plastic bags in a bin to be recycled separately from our curbside recycling. Companies like Trex use these collections to melt down and use in other products. Every time plastic is heated, it degrades in quality. This means that plastic can rarely be recycled 100% back into the product it started as.