A Life Cycle Analysis: A Plastic Fork

Living the Life of a Plastic Fork

Andrew Bernier – Prescott College

Sustainability Theory & Practice for Education

Fall 2011

Pramod Parajuli, Ph.D

 

 

Abstract

In this piece, the author conducts a thorough life cycle analysis of disposable plastic utensils. Components of research include fully investigating the origins of the materials needed, the process of producing the plastic utensil, the societal norms that have evolved around the product and what happens to the product after being discarded. Throughout the piece, ecological, economical and social implications of the plastic utensil economy (and the plastic industry as a whole) are discussed in the various stages of the life cycle of the plastic utensil.

 

 

Living the Life of a Plastic Fork

Background

Plastic cutlery is a part of my high school students’ lunchtime routine. The food is often served on a Styrofoam plate which is handed to the students along with a small plastic bag which contains a napkin, plastic fork, plastic knife and two small packets of salt and pepper. Well, they used to have the salt and pepper; I haven’t seen them included in a while. School budget cuts perhaps.

Everyday pizza is served as an alternative to the main meal that is being offered at the cafeteria. For some students, that is the way to go if the meal is not to their liking. For others, it is the only thing that they will eat that the school offers. Still, with the pizza that is traditionally eaten with only the hands, it is served with the plastic utensil pouch. This could be out of server habit or orders from the back of the kitchen, but typical pizza consumption styles (hands only) apparently are not regarded at the serving counter. Still, students take what is given, head to the table where their friends are sitting, eat (with or without the utensils), chat about the opposite sex for a little while, then collect the remaining inedible parts of their lunch (plate and utensils) and proceed to throw them into the trash, running hastily off to their next class; potentially mine.

When thinking about an object that had to be created from materials that had to be harvested, it can be disheartening to think that all that effort was made just to throw it in the garbage, sometimes never even taken out of the packaging. Not only that, but what happens to the object after it is discarded. If matter is neither created nor destroyed, what then what does happen to it? In this piece we will take an investigative look in to the complete life cycle and story of the common plastic disposable fork, from its humble beginnings to its all too often wasteful end. It is a story that we as consumers do not often get to see.

Introduction & History

Plastic forks (and plastic utensils in general) are highly regarded for the affordability and convenience. Typically found in take-out cartons, plastic forks are also available at most grocery, drug and convenience stores; nearly any commercial establishment that offers food of some type.

The concept of plastic itself was first created in the 1860’s, with Alexander Parkes creating Parkesine, an organic material derived from plan cellulose that could be heated then molded. A few years later John Wesley Hyatt took cellulose and combined it with camphor, a derivative of the laurel tree, and created celluloid, the first “durable” plastic that would retain shape (Bellis, 2012).

Plastic utensils were introduced in the 1940s, but did not start being mass produced until the 1950’s with two main causes: 1) The introduction of polypropylene and 2) the massive expansion of families into the suburbs after World War II (Polymer Plastics, 2000). When the baby boom generation started to take off, the demand for dining ware also grew. With the affordability and convenience of plastic utensils an attractive draw to growing families on modest budgets, many families included plastic utensils in their kitchen set along with metal-based dining utensils. Though metal was typically used during regular meals, plastic ware became popular for larger gatherings such as birthday parties and barbeques.

Those consumer habits have kept on, and with the growing popularity of take-out food, plastic utensils have become more of an expectation then an added convenience.  It is now customary to receive plastic utensils in a take-out package as opposed to having to ask for them. With how cheap plastic utensils have become, it is not seen as an added cost to the restaurants but more of an added convenience for the customer in hopes to retain their business. For cafeterias in public settings, such as hospitals and schools, it is cheaper to purchase disposable plastic ware as opposed to having to potentially replace silverware and pay for water & energy bills to wash the metal utensils.

Materials

Plastic utensils are typically made out of two types of plastics: polypropylene and polystyrene. Plastics are made from monomers and are produced from a process called polymerization. Monomers, single sequence molecules, such as ethylene and propylene are produced from natural gas and oil. Natural gas and oil, both fossil fuels, are hydrocarbons, or a series of molecules composed of carbon and hydrogen that are linked together in a repeating chain (Weisman, 2007). The natural gas and oil are heated to the point where the constituent hydrocarbons are converted into the reactive monomers (Romanowski, 2012). The monomers then become polymers (or multiple monomer molecules linked together) and are then cooled into blocks of the respective plastic they are designed to be come, depending on the additives put into the liquefied substance when the monomer conversion process takes place.

Polypropylene is a plastic based off the polymerization reaction of propylene monomers, which has a certain type of hydrocarbon molecular alignment that is different from other plastics. It is a preferred material to metal options because it is resistant to water, salt and acids; all of which can damage metal. Polystyrene has similar characteristics as it is has good chemical and temperature stability. It is formed from the polymerization of styrene monomers (Romanowski, 2012) and was originally produced in the 1930’s and was important to World War II in synthetic rubber production. Modifiers are typically added to both of these base polymers to improve the stability of the material and make manufacturing easier. Often, coloring agents are added to make the material more appealing than the typical colorless material that originally results in initial production. For example, the inorganic material titanium oxide can be included to produce the color white, which is the most typical color of plastic utensils.

Material

Purpose

Examples

Fossil Fuel

Raw material for hydrocarbons

Oil or Natural Gas

Monomer

Base polymeric material

Propylene, Polystyrene, Ethylene

Colorants

Produces Color

Titanium Oxide (White)

Plasticizers

Increases workability and flexibility of polymer

Paraffinic Oils, Glycerol

Stabilizers

Prevents breakdown of polymers during heating

Unsaturated Oils (ex Soy Bean Oil)

Protectors

Prevent Environmental Degradation

Ultra Violet Protectors, Antioxidants

Removal Compounds

Helps remove plastic from mold

Ethoxylated Fatty Acids, Silicones

                                                                                                Figure 1 (Romanowski , 2012)

Extraction

The number one ingredient in plastic is the hydrocarbon, which comes from oil or natural gas. Both of these materials, again fossil fuels, are typically found within the Earth’s crust. All fossil fuels are reflective of their name, as they are merely the remains of organic matter that existed millions of years ago. Living matter such as plants, animals, fungi; anything composed of cells, is compressed by the growing weight of the Earth’s crust, eventually changing from the solid form into a dense liquid, which is crude oil. Under continuous pressure, the material can change into another state of matter; gas. That gas, or natural gas, typically sits atop of oil deposits or exist on their own.

The extraction of crude oil is an intensive engineering process along with continuously growing in national and international contention. Oil can be extracted on either land or at sea. Land extraction typically consists of fields of many small oil wells, tapping into multiple points across an identified oil field. Off-shore based oil extraction is often done with large scale oil “rigs” or large floating platforms that are able to drill down below the ocean floor while resting on the surface, separated by hundreds of feet of water.

With local production of oil under constant debate, ranging from tapping oil deposits in wildlife reserves, building pipelines hundreds of miles and potentially hazardous water-based extraction (such as the Exxon Valdez shipwreck or the BP Deep Water Horizon Oil Platform explosion), the benefits of local oil production may soon be outweighed by the safety and environmental costs. In conjunction with the fears of having passed peak global oil production and international instability of oil extraction and control in the Middle East, acquisition of oil is increasingly coming into debate.

Natural gas, a fossil fuel that is receiving increased attention in lieu of the challenges surrounding oil, has recently fallen into its own contention as well. Natural gas is extracted though two main processes. The first is very much like an oil well, where a line is drilled into rock and gas is pumped out of a large natural gas pocket. The other is a process called hydraulic fracturing, also known as “fracking.” Fracking is where a line is drilled into bedrock where natural gas exists, but not in easily accessible pockets. A solution, consisting of mostly water and trace amounts of dissolving substances, is then pumped down into the bedrock. The hope is that the solution breaks apart the rock, releasing the natural gas. Once the gas is free, it can then be easily extracted.

That solution however, can seep into localized water sources, such as aquifers and wells. It has been well documented that homeowners with natural gas pumps on their property have been able to ignite their tap water due to the trace substances in the fracking solution being flammable. And recently the sudden occurrence of man-made earthquakes has been attributed to the fracking process (Joyce, 2012). When that solution is able to seep in between the layers of bedrock, it can act as a lubricant to allow the different layers of rock to slip past once another, releasing a tremendous amount of tension and stress, resulting in small earthquakes. The state of Ohio recently came to this conclusion and recently closed down all natural gas hydraulic fracturing production. This move still may not stop earthquakes from happening for quite some time as the liquid is still down there, but it now stops the natural gas industry and halts potential jobs and income for the state.

Production

After the fossil fuel has been extracted and refined, it is then shipped to the plastic production company, which is where the construction of the plastic takes place. After all of the specified materials are called upon for the specific plastic needed, they are processed together to create the polymer desired. Typically the basic form of the plastic is manufactured into small pellets, also known as “nurdles” (Weisman, 2007). Nurdles are the original form of which all other plastic forms are created from.

Nurdles are taken into the assembly line and often melted down into a liquid state, allowing for easier mass production of the utensil. The liquid is then formed and cooled into a malleable plastic sheet where the utensils can be easily cut but still retain shape. (See Figure 2). After the initial sheet has been used and plastic scraps are all that remain, the scraps are often collected and then reintroduced with new Nurdles to form another sheet. This is done to minimize waste.

Figure 2 (Romanowski, 2012)

            Utensils can then carry on down a production line where they are wrapped with other utensils in single use bags (as pictured) or can be placed in mass containers for consumer or industrial needs. The containers themselves are often also made of plastic or are cardboard boxes.

            Production companies for plastic utensils exist all over the world, but are most notably in the United States and China. Working conditions for companies vary on the regulations imposed by the country and company itself, but most are in a typical factory format with manufacturing lines made for product production and/or assembly. When the plastic resins are changed from solid to liquid via heating, the possibility for some of the chemical additives in the resins to become vapor is highly potential. Some have been known to be carcinogens, neurotoxins and reproductive toxins (ERI, 2004). Often times, the workers in these factories share similar characteristics; younger and of reproductive age, lesser educated, often poor and in many countries outside the United States, workers are female (Leonard, 2007). After prolonged exposure, plastic factory workers stand strong chance to absorb gaseous molecules and additives, increasing the risk of cancer, neurological effects or reproductive failure/abnormalities.

            The production of plastic for utensils is also an intensive energy and materialistic process, having a large environmental impact for the amount of product generated. In figure 3, the numbers for several factors are accounted for, calculating the demand of resources needed to produce one pound of either polypropylene or polystyrene, the two main plastics used in plastic utensil production.

Manufacturing      1 lb of material

Energy Used (kWh)

Water Used (gal.)

Solid Waste (lbs.)

CO2 Emissions (lbs.)

Polypropylene

9.34

5.12

0.029

1.67

Polystyrene

11.28

20.54

0.113

2.51

Figure 3 (Worldcentric.org, 2012)

            Even with rising costs of oil production and seemingly large amounts of resources needed to produce the product, prices for plastic utensils are kept low via working conditions and pay wages. Plastic companies originally established in the United States have moved to other countries with less stringent production regulations and lesser pay wages for employees, therefore reducing overall costs. (Leonard, 2007). These costs saving measures have allowed plastic utensil companies to keep prices for plastic ware lower than their wood and metal counterparts, making the like of the plastic fork a cheap and affordable option in the cutlery field. 

 

Distribution

Distribution is the process of getting the completed product to retail outlets. Plastic utensils follow very similar patterns of distribution as most other products, but the expansion of production to other countries has made means of shipping the product more complicated and energy intensive. Once the plastic utensil is created, placed in box or wrapped in further plastic before being placed in a box, sealed and then placed on a shipping crate, it is then ready to be distributed.

Typically, mass supply chain movement is handled by moving mass quantities of the product in transferable metal shipping containers, looking a lot like semi- tractor trailers. In our case, if the plastic utensil is produced at a plastic company internationally (let us say China), the most likely scenario is that the shipping crate will be placed onto a truck, where it is then driven to a port (if the production company is close enough to the ocean). From there, the crate is then transferred to an ocean liner and placed into one of the tractor-trailer like containers.

Surrounded by many more of those containers, the ocean liner takes off from the port to its destination, which could very well be a port south of Los Angeles, CA. From there, the crates are taken off the ocean liner via huge cranes and then placed onto a flat-bed train car. Once the train has as many cars filled as it needs to, it then takes off on the railroad to its next destination, say Phoenix, AZ. Once the trains arrive at the receiving yard just north of Grand Avenue and Indian School Road., another crane like device removes the container and places it where semi-tractor trailer trucks can then attach to the containers.

With the plastic utensil now on an 18-Wheeler, the truck heads to a company’s distribution center, for instance Safeway Grocery Stores. When the truck gets to the store, the containers are then emptied of the cargo crates inside. When emptied, the truck returns the container to the train yard where it is placed back on the train and heads back to port. The plastic utensil, still on crate, is then taken into the center where it is then inventoried and stocked.

When an individual outlet store, like a singular Safeway store, calls an order to replace their stock of plastic utensils, the supplies on the crate are then placed onto another truck and then taken to the store. When the utensils arrive at the loading dock of the store, they are taken off the truck and placed in the store’s stock until they are needed on the shelves where customers can pick up the utensils.

All along this “supply chain” are hundreds, if not thousands of workers; driving tucks, manning vessels, managing trains or directing train yards, stocking shelves, keeping inventory, etc. The amount of manpower that is needed to go into managing how plastic utensils (and just about all other consumer goods) is immense, requiring a wide variety and quantity of jobs that pay a wide pay-scale. The major reason why many jobs have been relocated to other countries is the cost of labor for workers. As mentioned in the materials section, the United States has minimum wage and high regulatory standards for workers, increasing the costs for producers to create their product. To avoid this, companies have places their manufacturing plants in other countries that have less stringent regulatory laws and low (if any) worker pay limits. Where costs for companies then go down, the costs for quality of life for the workers goes up, which can often keep people in a state of low-economic status or straight forward poverty (Leonard, 2007).

Though not only high amounts of human resources for jobs needed here, but shipping and receiving goods is a very energy intensive process. The best example to point out is the consumption of fuel to transport all of the goods. From ships, trains, trucks (and in some occasions airplanes), the movement of goods across the globe is a very energy intensive process. While there are some fleets that are moving to bio-fuels or natural gas, the overwhelming majority of plastic utensil supply shipment rests heavily on petroleum. We can’t specifically point out that plastic utensil shipment is solely responsible for petroleum use, as it is most often shipped with other products, but the burning of the fossil fuel adds to the carbon dioxide in the atmosphere, which is the main greenhouse gas that is attributed to the causes of global climate change.

Consumption

There is a big market out for plastic forks and other plastic utensils. In doing an internet search of both peer-reviewed articles and common articles, there was not a clear figure on how large the plastic utensil industry is as a whole on an economic scale. But, regardless of how much revenue plastic utensils generate, one of the biggest draws to plastic utensils is how cheap their up-front cost is to consumers. Again, reducing costs in labor wages and materials is a key way of how producers of plastic utensils are able to keep the prices of plastic utensils low.

There are hundreds of retail websites that sell plastic utensils, forks, knives, spoons, sporks, etc. of all different makes, models, chemical composition and toughness. Their costs are wide, typically depending on the durability, style and quantity. What I found was common was that many websites went on to describe the purpose and attractiveness of each style. There was one fork model that caught my eye, and its description read as follows:

With an elegant fluted handle design and sparkling metallicized finish, these Silver Visions 7" heavy weight plastic forks look just like fine silverware but are disposable for the ultimate in convenience! Perfect for weddings, parties, catered events and more, your place settings will look great, and you can simply throw them out afterward. Bulk packed. Sold 600 per case ($21.68 per case)” (Webstaurant Store. 2012).

            This quote ties perfectly back to the original point of how the attractiveness of plastic utensils lies with its convenience and affordability. With the notion of “you can simply throw them out” along with the many other descriptors of “single use” and “disposable,” it can be assumed that the average lifespan of a plastic utensil during its time with the consumer is a single use. If you wanted to give it an estimate, say 7-10 minutes, however long it may take to eat a piece of someone’s birthday cake or potato salad at a barbeque.

You may also have the extremes, such as folks who take the time to wash and reuse plastic utensils as many times as they can. Then again, you may have some of my students who are given the utensils still wrapped in the plastic bag, and are then swiftly thrown out without ever having been opened. Plastic forks retain their quality and strength (as we recall with the additives that are combined with the hydrocarbon resins), which means that we have many perfectly fine plastic forks now introduced into the waste stream.

One example of how the continuous buy, use, toss of plastic utensils can add up costs quick is the American-Speech Language Hearing Association office with an employee base of 225 people. They had plastic utensils available for lunch and a “green team” committee decided to eliminate the plastic utensils and go with reusable metal cutlery. They now save between three and four thousand dollars annually and not many employees seem to mind (Bhattarai, 2011).

 

 

Disposal

As is the original intention of plastic utensils being “disposable,” the ultimate destination for plastic cutlery is the trashcan. Now, technically the plastic types that make up most plastic utensils, polypropylene and polystyrene, are recyclable, but most recycling plants do not accept them because they are cumbersome to process and not cost effective per unit. Because of that, most plastic utensils follow a fate of either being placed in a landfill or incinerated.

When the plastic utensil is thrown away, it will sit in the trash for a bit, make its way to a larger receptacle, which will then get collected by a garbage truck and then brought to the local (or in some cases hundreds of miles away) landfill. Once the utensil arrives at the landfill, there are typically two options that the utensil can take; the first is to be placed into a landfill or the second is to be incinerated.

If the fate of being placed in the landfill is chosen for the utensil, it can be hermetically sealed for decades, receiving little opportunity to decompose, if at all. The molecular linkages in plastics is incredibly strong, and with the addition of some of the additives such as the protectors mentioned in the materials section, the breaking of the molecular bonds to actually decompose the fork takes an incredibly long time. Landfills are structured in a way that seals oxygen out from the material inside. Without oxygen, let alone UV rays from the sun along with wind and water erosion, the breakdown of trash, let alone a plastic utensil, is near impossible. The only thing at that point that could break down the plastic material would be anaerobic bacteria, or bacteria that do not require oxygen to breakdown matter. At that point, the utensil and other trash around it would start to turn into this sludge-like substance, flow down to the bottom of the landfill where at some point it could potentially leech into ground soil and ground water through a crack in the casing of the landfill. That crack would develop over time as even the molecules in the substance, such as concrete, would also breakdown as more time passed. And even though the utensil may no longer have its original shape, the hydrocarbons and additives that made it up would still persist in the sludge, possibly contaminating the surrounding soil and groundwater and affecting the communities and families dependent on those resources. A potential “benefit” though from this is the collection of methane gas, which is another product of anaerobic decomposition, which can also be collected and used as a natural gas source.

The other potential option is incineration. As plastic is made from hydrocarbons, which is what fossil fuels are made of, it has the potential for releasing a good amount of energy by breaking the carbon bonds that were from the original crude oil. When heat is applied to the utensil and it combusts to release the energy stored in the carbon bonds, it also produces the products of carbon dioxide, water and non-toxic ash (Romanowski, 2012). After the carbon dioxide and water has been released, the ash is typically then placed into a landfill (Leonard, 2007). The energy produced from burning the plastic utensil along with other trash is harnessed and relayed into the energy grid, much like a power-plant, and could be sold back to energy companies for contributing electricity to the grid.

Since the 1950s, one billion tons of plastic have been discarded and may persist for hundreds or even thousands of years (Weisman, 2007). The mindset of disposable and single use plastic utensils has contributed to this in great capacity, and it does not show many signs of stopping. Then again, the supply of this “trash resource” has now become an economy in itself, by generating both jobs to manage the large load along with the energy it creates. Although the plastic utensil might be the ultimate in convenience and affordability, the life cycle around it is quite complex and we may not be able to afford the ecological and social costs if we keep using them, or if you are one of my high school students, not use them.

References

Bellis, Mary. The History of Plastics: Timeline of Plastics. (2012) http://inventors.about.com/od/pstartinventions/a/plastics.htm

Bhattarai, Abha. Life at Work: Giving Up Plastic Utensils. (2011). The Washington Post. Capitol Business.

Environmental Road-Mapping Initiative (ERI). Plastics: Impacts, Risks and Regulations. (2004) National Center for Manufacturing Sciences. http://ecm.ncms.org/ERI/new/IRRplastics.htm

Joyce, Christopher. How Fracking Wastewater is tied to Quakes. (2012). Washintgton, D.C. National Public Radio. http://www.npr.org/2012/01/05/144694550/man-made-quakes-blame-fracking-and-drilling

Leonard, A. (2007). Story of Stuff. www.storyofstuff.com

Lewis, A. The Life of a Plastic Fork. (2010). Brooklyn, NY. The L Magazine.

McDonough, W. & Braungart, M. (2002). Cradle to cradle: remaking the way we make things. New York: North Point Press.

Polymer Plastics Company, LC. 2000. History of Plastics.  http://www.polymerplastics.com/history_plastics.shtml

Romanowski, P. Spork. (2012) www.madehow.com/Volume-7/Spork.html

Watson, M. Materials Awareness.  University Centre Yeovil. http://arts.brighton.ac.uk/__data/assets/pdf_file/0012/6006/Materials-Awareness.pdf

Webstaurant Store, The. http://www.webstaurantstore.com/silver-visions-7-heavy-weight-silver-plastic-fork-600-case

Weisman, Alan. The World Without Us. (2007). NY. St. Martin’s Press

Worldcentric.org. (2012) “Energy Savings” http://www.worldcentric.org/sustainability/energy-savings

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