The Global Scale of Plastic Pollution

Plastics are globally distributed, and present in significant levels as marine pollution in every ocean on the planet (Eriksen et. al. 2014).  They tend to collect in higher concentrations in the sub-tropical gyres of the world's oceans (Moore 2001, Eriksen 2013). A gyre is a large system of circulating ocean currents.  Their whirling pattern causes a higher density of ocean debris to collect, including plastics (Moore 2001, Eriksen 2013). Many of you may have heard of the Great Pacific Garbage Patch, plastic island, trash island, or garbage island. These terms are all referring to two gigantic patches of marine debris, one on either side of the gyre in the northern Pacific Ocean. So there isn't literally an island that you could walk around on, it's just a massive concentration of trash in the ocean.

Ocean Gyres. This image shows the five major ocean gyres.  They act like giant whirlpools, collecting higher quantities of plastics.

Imagery by NOAA

In 2014 Eriksen et al published a paper modeling the amount of plastic in the world's oceans, by count and by weight.  They conducted wide scale sampling of surface plastics in every ocean, and then used a statistical model to determine the most probable distribution of plastics throughout the sea. These models took into account oceanic circulation and currents, as well as the size and weight of the plastic pieces.

Based on their model, they conservatively estimated:

"at least 5.25 trillion plastic particles weighing 268,940 tons are currently floating at sea."

- Eriksen et. al. 2014

How much is that?

5.25 trillion seconds is equal to 166,000 years - 166,000 years ago homo sapiens had just started to wear clothing (Toups et al 2010, Wu et al 2012)

268,940 tons is 10 times the weight of The Statue of Liberty and 20 times the weight of the Eiffel Tower!

Here are the maps they generated to show the distribution of those plastics:

Above: Model results for global plastic count density in four size classes. (Eriksen et. al. 2014)

The numbers in the lower left of each picture indicate the size class of plastic being looked at, the bar on the right indicates the projected count density. Red is a higher plastic count, blue is lower.

Above: Model results for global plastic weight density in four size classes. (Eriksen et. al. 2014)

The numbers in the lower left of each picture indicate the size of plastic being looked at, the bar on the right indicates the projected weight density. Red is a higher plastic weight, blue is lower.

The implications of this study are that plastics are globally pervasive in marine environments. This plastic soup is unavoidable for marine life, and could have incredibly drastic effects on the health of marine ecosystems.

How Plastics Affect Marine Life

A Laysan Albatross chick rests on a small derelict fishing net. | Photo Credit: NOAA Coral Reef Ecosystem Program

Ocean plastic impacts marine animals of all sizes, and causes marine life harm in three major ways: entanglement, ingestion, and toxicity.  Marine animals including turtles, penguins, seabirds, whales, dolphins, seals and sea lions, manatees, otters, fish, and crustaceans have all been documented as being affected by either entanglement or ingestion of plastics (Laist 1997). 

Seal trapped in ocean plastics | Photography by Nels Israelson

Entanglement:  Larger plastics (like six-pack carriers, plastic packing materiel, netting, etc.) can easily entangle marine life, and overtime can cause harsh skin wounds, suffocation, and inability to escape predators (Gregory 1991).  

Ingestion: Many marine vertebrates have a consistent record of consuming plastics in the ocean (Gregory 2009). Sometimes plastic bags are mistaken for jellyfish, other times plastic pellets are consumed by fish, and moved up the food chain when birds, seals, and other predators eat those fish (Gregory 2009). Seabirds have a very well documented history of plastic ingestion (Laist 1997). To grasp just how much plastic is consumed by sea life, refer to the case study below.

Toxicity: Toxicity can go hand in hand with ingestion.  There are certain types of pollutants that can be absorbed by living things, these are called "persistent organic pollutants" (Eriksen et. al. 2014). These pollutants are either present in plastics from manufacturing or absorbed from the environment and transferred to the tissues of animals through ingestion (Teuten et al 2009).   The accumulation of these harmful chemicals, and their negative impacts has been observed in different types of marine life (Tanaka et al 2013, Wright et al 2013).

Northern Fulmars and Plastic Ingestion

Photography from the U.S. Fish and Wildlife Service

Northern fulmars (Fulmarus glacialis) are a seabird which highly resemble seagulls, but are actually closely related to albatross. They are found in the Northern Atlantic and Pacific Ocean regions and  live at sea their whole lives.

 The International Council for the Exploration of the Sea (ICES) determined that the amount of plastic found in Fulmar stomachs is a reliable way to monitor plastic litter at sea (OSPAR, 2006). The critical amount of plastic for this species (defined by OSPAR Ecological Quality Objective) is no more than 10% of fulmars exceeding 0.1 g of plastic in their stomachs (Van Franekera et al 2011) and the ideal scenario is "less than 2% of northern fulmars (Fulmarus glacialis) having ten or more plastic particles in the stomach" (OSPAR, 2006). In a study done by Van Franekera et al it was found that 95% of sampled northern fulmars had plastic in their stomachs, 58% of those exceeded the critical level of 0.1 g, and the average amount of plastic found in the bird stomachs was 35 pieces weighing .31 g (Van Franekera et al2011).

Photography by AWeith

So, what we can gather from this particular case study? The big take away is that plastics were present in the stomachs of nearly every one of these birds. The majority of the birds that consumed plastic had ingested about 3x above the critical level. 

The fulmars serve as an indicator species in this instance, meaning they represent a specific ecological condition.  That ecological condition is: there is far too much plastic in the ocean, and it is dangerous to marine life.

Photography by Francesco Veronesi

What are Microplastics?

Plastic microbead from face wash, 0.5 mm wide | Imagery from Andrew Watts, Face to Face with Plastic, original source University of Exeter from United Kingdom

What are microplastics?

Microplastics are plastic pieces/pellets that are less than 5 mm (.2 inches) in diameter, which is slightly larger than a grain of sand (Wright et al 2013). We know that micro plastics are present throughout the world in all its oceans. 

why do microplastics matter?

The two major concerns surrounding microplasits are that 1)"they can be ingested throughout the food web more readily than larger particles" (Wagner et al 2014) and 2) there has been very little research done on the biological effects of micro plastic ingestion, and freshwater microplastics (Wright et al 2013, Wagner et al 2014, Outi Setälä 2014). 

Will microplastics ever decompose?

No. That's the problem. In all honesty, we don't have good estimates on how long it will take traditional plastics (as opposed to bio-plastics) to truly decompose. They just break down into smaller and smaller pieces, and it could take anywhere from hundreds to thousands of years for them to completely break down.

what products Contain or create microplastics?

Anything made from plastic can become marine litter and turn into microplastics.

What are Microfibers? 

Microfibers are a type of microplastic which originate from synthetic textiles (such as nylon, polyester, rayon, acrylic or spandex).  Washing your clothes that are made of these synthetic materials causes them to shed microfibers, which go down the drain in the washing machine and become plastic pollution.

What do microplastics look like?  

Check out the images below. These microplastics were all collected in the tributaries of the Chesapeake Bay, images made available by the Chesapeake Bay Program.  

Microplastics from the Patapsco River

Microplastics from the Rhode River

Microplastics from the Patapsco River

Microplastics from the Patapsco River

Microplastics from the Patapsco River

Microplastics from the Patapsco River

Microplastics from the Patapsco River

Microplastics from the Patapsco River

Microplastics from the Patapsco River

Microplastics from the Patapsco River

Microplastics from the Patapsco River

Microplastics from the Magothy River

The images above were pictured at the laboratory of Dr. Lance Yonkos in the Department of Environmental Science & Technology at the University of Maryland in College Park, Md. Microplastics were collected by the National Oceanic and Atmospheric Association Marine Debris Program via a manta trawl in four tributaries feeding into the Chesapeake Bay. A study led by Yonkos reports that the prevalence of microplastics in the watershed is positively correlated with population density and proportion of development.

What Can i do to prevent microplastic pollution?

The easy answer is to reduce your plastic footprint. Here are some easy ways to do so:

• Say no to disposables: if you're only going to use it once, you don't need to use it.
  • coffee cup - bring a travel mug, your drink will maintain its temperature better and you'll generally save a little on your drink too
  • grocery bags - buy reusable bags, both for carrying all your stuff in AND for your produce
  • plastic wrap - either buy or homemake beeswax wrap, I promise it works just as well (and smells nice too!) 
  • disposable cutlery - I carry a metal spork around with me, but even just having a fork or spoon kicking around your purse or car is a good idea!
  • straws - stainless steel / bamboo / glass / silicone straws for life! Ask for your next drink with "no straw, please!" and bask in the zero waste glory!
• Clothes: Buy natural, buy secondhand.
  • Do your best to purchase clothes made from natural fibers like cotton, wool, silk, linen, hemp, flax, etc. And when you wash your clothes that are not made of natural fibers, place them in a fiber filter bag. 
• Cosmetics: Refuse microbeads, beware long named ingredients.
  • Choose personal cosmetic products that contain no microplastic ingredients.  Beat the Microbead has an awesome list to help you figure out which products are safe for use.
• Food: Cook more, say no to packaged food.
  • Generally speaking, cooking at home is healthier for you. But if you do eat out, bring your own tupperware!
  • Saying to to packaged food is also generally a healthier practice, since it reduces the amount of highly processed food you're eating.
• Recycle Right: This is obvious, but not always so easy.
  • Recycling is great, but you need to actually do it and do it right for it to count! You can read my post on how to recycle right, and look up recycling in your area on Earth911.org’s recycling directory.

Plastics In the Foodchain

Photography by Alberto_VO5

what is a food chain?

A food chain is a description of who eats who in the wild. Things like plants and herbivores are low on the food chain, whereas predators and decomposers are high on the food chain. 

How do plastics enter the food chain? 

Because many plastic particles are so small (see microplastics), they can and are being ingested very low on the food chain (Wright et al 2013, Outi Setälä 2014).  It has also been confirmed that microplastics have the ability to move up the food chain at incredible low levels, i.e. from mesozooplankton to microzooplankton (Outi Setälä 2014).  This implies that microplastics could accumulate in aquatic food webs, which is potentially hazardous to both ecological and human health.

How do plastics accumulate in the food chain?

When pollutants enter the food chain, their concentration increases from one link to another. 

You can see in the pyramid diagram below how this works. The pollutant (red dot) starts out in a low concentration in the first pyramid section.  As you move up the food chain, or pyramid, the concentration of the pollutant becomes higher.

Imagery by Martin-rnr

Freshwater Plastic Pollution

Small plastics collected by a Dutch researcher, Gijsbert Tweehuijsen, while researching plastics in runoff waterways which would inevitable end up in the sea (2013).

Freshwater habitats like lakes and rivers are affected by plastic pollution too, but the research surrounding these critically important habitats is lacking (Wagner et al 2014).  When our freshwater systems are effected by plastics, they have an impact on both terrestrial and marine system.  Hazardous chemicals present in plastics can leach from waste disposal sites into ground and surface water (Teuten et al 2009) reaching municipal waters and eventually the ocean.