Session A5
Paper #41
Disclaimer — This paper partially fulfills a writing requirement for first year (freshman) engineering students at the
University of Pittsburgh Swanson School of Engineering. This paper is a student, not a professional, paper. This paper is
based on publicly available information and may not be provide complete analyses of all relevant data. If this paper is used
for any purpose other than these authors’ partial fulfillment of a writing requirement for first year (freshman) engineering
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FROM PRAWNS TO PLASTIC
Natalie Pyle, [email protected], Mena 1:00pm, Ava Chong, [email protected], Mena 1:00pm
Abstract— Our carbon footprint is rapidly increasing due
to the overproduction and treatment of our waste
products. Specifically, the plastic that makes up most
consumer product packaging and food waste are the
biggest culprits. While it is difficult to completely change
current plastic production and wasteful food practices,
recent research has led engineers to discover an
environmentally friendly and sustainable plastic that
degrades quickly and is a shellfish byproduct.
This material, called chitosan, not only replicates
plastic packaging, but can also increase the shelf-life of
food, leading to less food waste globally. Chitosan, a form
of chitin, is a natural and biodegradable polymer found in
the shells of shrimp, crabs, and other crustaceans.
Chitosan flakes are extracted from the chitin and mixed
with a polymer film to create a bioplastic that can be used
for shopping bags, food packaging, and diapers. Chitosan
could help solve the problems of food waste and the
abundance of plastic in our oceans and landfills that is
harming our ecosystem. Chitin is the second most
abundant organic compound, meaning that the potential
for chitosan use is great. Currently, there are very few
ethical concerns with this process. Because chitosan only
uses the byproduct of shellfish it will most likely not
further increase overfishing.
This technology is incredibly important because it
incorporates sustainable practices that will not deplete
existing resources. It provides a product that has the
potential to decrease plastic pollutants and food waste
pollutants in a way that does not harm the environment or
people. The effects of past unsustainable practices are
rapidly becoming irreversible. It is vital now more than
ever that we prevent future damage to our ecosystem
before it is too late.
alternative to petroleum-based plastics has been
recognized and researched across the globe in recent
decades. Plant-based biodegradable products have been
produced, but not without issue. Many plant-based
products do not replicate the type of plastic currently in
use, have a high production cost, and are still bad for the
environment due to the toxic chemicals used in
production [1]. The continued push to find better plastic
alternatives is further accelerating research on more
sustainable technologies. One of the most promising
sustainable solutions currently being researched is
chitosan. It comes from chitin, a natural and
biodegradable polymer found in the shells of crustaceans
such as shrimp, crabs, prawns, and lobsters. Chitosan
technology, if incorporated correctly, has the potential of
becoming an answer to the problems of plastic and food
waste and pollution. This paper will look at chitosan
production and implementation as a sustainable solution
for the planet. We will define sustainability as practices,
technologies, developments, and ideologies that work to
improve and protect the environmental, societal, and
economic needs of present and future generations. The
paper will place a particular emphasis on the development
of environmentally sustainable technologies that will
benefit present and future generations.
The Problem with Plastic Pollution
Approximately 300 million tons of plastic are
produced globally every year [2]. The modern era of
plastics dates back to 1907 with the development of a
synthetic polymer called Bakelite created by chemist Leo
Bakeland [3]. Bakelite led the way for a deluge of plastics
that include PVC, nylon, and polyethylene plastics
produced from the chemicals extracted from fossil fuels.
Historically, plastics have been inexpensive and easy to
produce, flexible to mold into any shape, and strong
enough to be durable and long lasting [3]. However,
plastic waste such as bottles, toys, and packaging can take
centuries to decompose, with a plastic bottle taking an
average of 450 years [4]. According to the United Nations
Environmental Program, between 22 and 43 percent of
plastics end up in landfills [5]. A large percent of plastic
waste from the United States and Europe is shipped
overseas to China where a lack of environmental
Key Words—Biodegradable, Bioplastic, Byproduct,
Chitin, Chitosan, Plastics in packaging, Sustainability
GLOBAL WASTE: THE PLASTIC AND
PACKAGING PREDICAMENT
It has become increasingly apparent that the
current proliferation of plastic and food waste is
unsustainable and damaging to our environment. The
need for a biodegradable, environmentally friendly
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Ava Chong
protection controls promotes improper disposal and
burning of plastics that worsen an already existing air and
water pollution problem [5]. This practice is not only
harmful to the environment but to the people who
unknowingly partake in it. Because waste is shipped
overseas, the people creating the waste often do not see
first-hand the negative effects of their waste and are
therefore not nearly as concerned with the effects as they
should be.
If not seen directly, it is often hard to understand
that throughout the world, landfills are filling up, taking
valuable land and creating a toxic environment. As
landfills pile up, buried plastics slowly decompose,
leaching toxins such as BPA (Bisphenao A) into the
ground and water sources [6]. These are toxins that are
known to have adverse effects on the health of humans
and animals. The increasing spread of health risks that
these toxins pose on humans and wildlife has proved that
toxins should not be taken lightly.
Plastics are not just a problem for landfills.
Worldwatch Institute estimates that 10 to 20 million tons
of plastic end up in the ocean [5]. This can be seen in the
Pacific Trash Garbage Patch, a well-documented massive
collection of debris in the North Pacific Ocean. It floats
around the world, collecting more garbage along the way.
Plastic pollutants make up a large part of this garbage
patch. One of the major pollutants of this vortex of
garbage comes from microplastics, smalls particles of
plastic pollutants that have partially decomposed from
sunlight and weather [7]. These microplastics present a
danger to marine life that ingest the particles that contain
the toxic chemicals found in the plastics such as PCBs
(polychlorinated biphenyls), pesticides, and BPA. When
fish and other marine life digest these plastics, they are
eventually added to the food chain for human
consumption. These chemicals have been linked to
hormonal disruptions, cancers, growth abnormalities, and
other health issues [6]. This massive layer of garbage in
the Pacific also prevents sunlight from reaching the
bottom of the ocean, disturbing the growth of plankton
and algae causing additional disruptions to the underwater
food chain [7].
Below and above water, on beaches and shores,
plastics have been polluting and causing environmental
and economic damages. Cleaning the plastics from our
landfills and oceans is a monumental task, and one that is
not sustainable if we keep manufacturing plastics that are
not biodegradable. The economic, environmental, and
societal costs are too great to continue with petroleum
based plastics.
environmental and economic consequences. Every year,
about one-third of food produced for consumption goes
unused, leading to about 1.3 billion tons of waste annually
[8]. Not only is this extremely wasteful, it also hurts the
economy. Food waste causes industrialized countries to
lose around $US 680 billion annually, and around $US
310 billion in developing countries [8]. There are
numerous explanations for the massive amounts of food
waste. The Food and Agriculture Organization of the
United Nations has determined that food loss in
developing countries often occurs at the early stages of
production because of mismanagement [9]. Often times
the early processes are not perfected and the loss of food
amounts from the erroneous production, harvesting,
storage, packaging and transportation of the food. Food
waste in “medium and high income” or industrialized
nations such as the United States, occurs at later stages of
the food supply chain that includes industries, retailers,
markets, restaurants, and consumers [9]. The study states
that in “medium and high income” nations it is often a
matter of food production exceeding demand that causes
food waste [9]. The food waste in industrialized nations
can occur at factories when food that doesn’t meet
standards is thrown out instead of recycled or reused. In
supermarkets, foods that have reached their expiration
date are often thrown away instead of sent to a wholesaler
or foodbank. Fruits and vegetables that are bruised or
nearing spoilage are often thrown out and not donated to
food banks or sold at reduced prices. Leftover food from
restaurants and institutions such as schools and hospitals
are thrown in dumpsters instead of compost piles. In
addition, there is the food waste created by consumer
households. While refrigeration and plastic packaging has
extended the shelf life of products, it has also increased
the capacity for food storage which leads to food waste.
These practices, which are common in the industrialized
countries, account for staggering statistics on food waste.
It’s estimated that the average American household
throws out approximately 25% of the food and drinks that
they purchase [10]. The following diagram shows the how
much food is wasted per year in various countries.
Food Waste
FIGURE 1 [9]
Per Capita Food Losses and Waste
Food waste is a global issue that has severe
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removed, it is washed and dried and crushed into smaller
pieces called chitin flakes. After obtaining the chitin
flakes, the next step is demineralization, which involves
soaking the flakes in order to remove excess minerals and
then rinsing and draining them. After demineralization,
the actual production of the chitosan occurs during
deacetylation, or the removal of an acetyl group. During
this step, sodium hydroxide is added to assist with the
deacetylation and the flakes are boiled [12]. Then they are
rinsed and oven dried, creating chitosan flakes. The final
step in chitosan production is purification, which makes it
acceptable for use. The three steps for purification are the
removal of insoluble parts through filtration,
reprecipitation of chitosan by using sodium hydroxide,
and demetallization of retrieved chitosan. Once all of
these steps have been completed, the chitosan is ready for
use [12].
Chitosan can be made into many different types
of plastics, but chitosan-based plastics are not all the
same. Different research institutions around the world are
developing types of chitosan-based plastics that all vary
slightly from each other. These variations are mostly in
the physical properties of the plastic. One notable
example of an early model of chitosan bioplastic is
“Shrilk”, a fully biodegradable plastic laminate developed
by the Wyss Institute in 2011 [2]. In order to make the
durable Shrilk, the chitosan is layered with fibroin, a
protein derived from silk [2]. However, this mixture is not
waterproof, which is a crucial feature of traditional
plastics. In later variations of Shrilk, a beeswax coating is
added to produce a waterproof barrier [13].
The Shrilk is durable and renewable, allowing it
to replace conventional, sturdy, three-dimensional
plastics. It can also be used to make trash bags,
packaging, and diapers [13]. Researchers at the Wyss
Institute believe that once the Shrilk is ready for molding
into plastic products, only minor modifications to existing
plastic manufacturing plants will be needed to
accommodate this new material [13]. The extraction
process is currently being researched and modified with
the goal of having a more sustainable fractionation
method, such as one that is solvent-free and minimizes
waste [14]. With additional research, this solvent-free
process should be attainable [14]. With these changes,
Shrilk can meet the criteria for economic sustainability.
Plastic products made with Shrilk instead of the
old petroleum-based plastics will fully decompose in just
a few weeks. In landfills, the Shrilk plastic degrades and
releases nutrients into the soil, encouraging plant growth
in just three weeks [15]. It is also important to note that
both chitosan and the fibroin are used in FDA approved
products, meaning the Shrilk and other chitosan-based
bioplastics are a safe plastic alternative [2].
In addition to Shrilk, other chitosan-based
It’s apparent that food waste is costly and has
economic ramifications for businesses and consumers.
What isn’t as apparent is the cost that waste has on the
environment. Food packaging and waste ends up polluting
oceans and landfills. Approximately 23% of methane
emissions come from decomposing food in landfills. [10].
The significant amount of human made methane gas is
not sustainable since methane is one of the leading
contributors to global warming. It is crucial that we
initiate a solution to reduce these emissions and decrease
the harmful impact on our planet. For the amount of
energy and production that goes into most food, the
staggering amount of food waste is that much more
detrimental.
A SUSTAINABLE PLASTIC FOR THE
FUTURE
The Production of Chitosan
Chitosan-based plastics have the potential to be
the sustainable technology that helps alleviate the
environmental damage caused by plastic and food waste
pollution. The production of chitosan is a complex
procedure that has many stages. Chitosan is derived from
the organic compound chitin, a tough polysaccharide,
found, as mentioned, in the shells of crustaceans like
shrimp, crabs, and other shellfish products. As shown in
the graph below, chitin is one of the three chemicals that
can be extracted for industrial use. Although it is derived
from a naturally occurring organic compound, chitosan is
a man-made polymer [11].
FIGURE 2 [14]
Shell Biorefinery
The chitosan is produced using the chitin in the
crustacean shells through several steps. The first step is
extracting the chitin from the crustacean shells. Once
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plastics are under development. At the University of
Nottingham, researchers have partnered with the Nile
University of Egypt to create eco-friendly shopping bags
from chitosan [16]. Egypt, like other countries around the
globe, is dealing with the environmental outcomes
attributed to dumping of plastics, especially illegal dump
sites [16].
crustacean shells.
Chitosan is produced as a partially de-acetylated
form of chitin, allowing the chitosan to be water soluble.
Although either acids or alkalis can be used to deacetylate
chitin, alkali are used more frequently [18].
Many parameters in the deacetylation reaction
can impact the characteristics of the final chitosan.
Numerous studies have been conducted on these
parameters, and they have indicated that molecular weight
and deacetylation of chitosan are significantly affected by
NaOH concentration, reaction time, temperature, and
repetition of alkaline steps. Additional factors such as
reaction reagent, atmosphere, particle size, chitin to
solvent ratio, and source of raw materials were also tested
in other studies [18].
The chemistry behind chitosan allows it to be
versatile when creating products. However, the sensitivity
of the chitosan requires careful processes to create the
optimal result. With detailed control over the outcome of
the plastic product, the plastic formula can be perfected
with much precision [14].
The properties of chitosan, such as its
biocompatibility and biodegradability make it very
beneficial for food preservation and packaging. The use
of chemical preservatives can be avoided, and edible
antimicrobial films can be produced due to the food film
forming properties of chitosan. It’s antimicrobial and
antioxidant properties do not migrate easily out of the
protecting film [16].
Scientists from the Wyss Institute for
Biologically Inspired Engineering have studied the
molecular characterization of chitosan film, which has
revealed the existence of millimeter-scale liquids crystal
domains that rearrange when stretched. In attempting to
develop a chitosan-based material suitable for
manufacturing uses, Javier Fernandez, Ph.D., found that
the molecular geometry of chitosan is very sensitive to the
method used to formulate it. The resulting mechanical
properties of the material can be either brittle and opaque,
which makes it unusable, or pliable and transparent,
which is the intended outcome [19]. Chitosan’s unique
structure and chemical properties make it an incredibly
beneficial and sustainable alternative to current plastics.
The Chemistry Behind Chitosan
The reason chitosan-based bioplastics are an
optimal plastic alternative lies within the chemistry of
chitin and chitosan.
FIGURE 3 [16]
Chemical Structure of Chitin
Chemically, chitin (C8H13O5N) is a natural longchain polymer of an N-acetylglucosamine, a derivative of
glucose [16]. Chitin is the second most abundant organic
compound in the world after cellulose [15]. The structure
is comparable to cellulose, in which the C-2 hydroxyl
group is replaced by acetamido residue [17]. In its natural
form, chitin occurs as ordered crystalline microfibrils
which allow for the formation of strong structural
components in the shells of shrimp and other crustaceans.
Chitin is composed of molecular chains that are organized
in sheets and held by intra-sheet hydrogen bonds that
prevent diffusion of small molecules, making chitin
insoluble in water and other similar solvents [18].
The natural chain-like structure of chitin makes it
very suitable for interchain hydrogen bonding, adding
strength to the new material. For example, chitin is
combined with a protein matrix in a laminar, plywoodlike structure to form sclerotin, the component responsible
for the armor-like strength of insect cuticles.
Crustacean shells are 20-40% protein, 20-50%
calcium carbonate, and 15-40% chitin. Chitin is found
within the shells as a component of a complex network
with proteins onto which calcium carbonate is deposited.
In industrial processing, chitin is extracted by acid
treatment to dissolve the calcium carbonate, followed by
alkaline solution to dissolve proteins. In addition, a
decolonization step is often added in order to remove
pigments and obtain a colorless, pure chitin [18]. Shrimp
shells are advantageous to use for chitin isolation since
the walls of shrimp shells are thinner than other
THE BENEFITS OF A BIODEGRADABLE
PLASTIC
Shelf-life of Food
As discussed earlier, food waste has a severe
impact on both the environment and the economy. In
order to provide a solution, current research is being
carried out that would allow for an increase in food shelf4
Natalie Pyle
Ava Chong
life. One way to achieve this is by creating a chitosanbased plastic specifically for food packaging, since one of
the many benefits of chitosan is its natural anti-microbial
properties. To achieve this, an active polymer film that
absorbs oxygen must be added [11]. If successful, this
oxygen absorbing packaging would increase shelf-life
with high efficiency and low energy consumption [11].
For example, a recent study was done to see
how a chitosan-based packaging could limit
contamination of “ready-to-eat” meat products with
Listeria monocytogenes. In order to prevent the
contamination, antimicrobials such as sodium lactate,
sodium diacetate, potassium, potassium sorbate, and
sodium benzoate were incorporated into the chitosan
plastic. Results showed that adding these antimicrobials to
chitosan packaging would have “excellent long-term
antilisterial effects” and hold the potential to be used as
meat packaging in the future [20].
Other research is being done by the National
University of Singapore to fortify chitosan-based
composite film with grapefruit seed extract (GFSE). This
alternative plastic has strong antioxidant, antiseptic,
germicidal, antibacterial, and antiviral properties.
Specifically, it would slow down fungal growth, hence
doubling the shelf-life of perishable foods. This film like
plastic not only has antifungal and antibacterial
properties, but has incredible strength and flexibility. It
also improves shelf-life due to its ability to block
ultraviolet light, slowing down the degradation process
[21].
Another potential way to increase food shelf-life
is by using chitosan as a natural food preservative.
Chitosan has antimicrobial properties that would fight
against a wide range of food borne filamentous fungi,
yeast, and bacteria. Chitosan also has film-forming
properties that can be used as edible films or coating. This
would allow for perishable goods to be stored for longer
by modifying the internal atmosphere as well as
decreasing the transpiration losses [22]. By increasing the
shelf-life of food goods, we lessen the unsustainable
damage done to the environment and economy by food
waste.
degradable. Also, the use of plant-based bioplastic is
limited to packaging material and simple food and drink
containers [15].
The chitosan in the bioplastic gives it the
biodegradable property that allows it to decompose in just
a few weeks [21]. Another current problem with plastics
is that when they are discarded into the environment, their
toxic chemicals such as BPA are discarded as well. These
toxins disrupt natural cycles in the environment and can
pose health risks to many animals. The rate that we are
exposing toxic chemicals to the natural world is too high
for the environment to counterbalance. Chitosan-based
biodegradable plastics also contain few to no toxic
chemicals [21]. This would drastically decrease the
amount of waste in our landfills and the amount of toxic
chemicals that are released into the environment.
Chitosan-based bioplastics also can act like a fertilizer
and return rich nutrients that support plant growth to the
soil when they are completely degraded. In one study, a
California black-eyed pea plant grew within three weeks
in chitosan plastic enriched soil [15]. The biodegradable
processes of chitosan-based plastic surpass anything of
current plant based bioplastics and have a significantly
better effect on the environment.
In terms of the economic sustainability, the raw
material to produce chitosan-based products costs
significantly less than the fossil fuels needed for
traditional plastics. This is because the main source for
extracting chitosan is shellfish waste that is plentiful and
inexpensive. One ton of dried shrimp shells is currently
valued at only $100 to $120 per ton [14]. The vast
majority of shrimp shells are often completely discarded
or turned into fertilizer. A worldwide industry for
extracting chitin and producing chitosan can be an
economic advantage to many areas of the world. With
additional research and funding, the fractionation process
can become more efficient and sustainable.
Eventually, the increased use of chitosan-based
bioplastics will lower carbon emissions and reduce
packaging waste accumulating in landfills and oceans. It
can also promote foreign trade through the development
of the market for shrimp and other crustacean shells [8].
A Positive Environmental and Economic Impact
ETHICS AND CONCERNS
A move forward in Shrilk and other bioplastic
materials would rapidly decrease the turnover for waste
products. Currently, it can take up to thousands of years
for some plastics and packaging to decompose, while
bioplastics, including chitosan, take less than half of that
to decompose. Even more detrimental to the environment
are plastics that are made with polyethylene terephthalate
(PET or PETE) that will never biodegrade [4]. A current
problem with plant-based bioplastic is that it is not fully
Overfishing
The production of chitosan requires a substantial
amount of chitin, the main component in the hard shells
of shellfish [15]. Because this requires a large amount
shellfish, the concern with overfishing of shrimp and
other crustaceans may arise. The debate about where the
line is drawn to claim that overfishing is a problem has
been going on for decades [23].
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In recent years, there has been a particular
emphasis on the damage caused by the overfishing of
shrimp. The effects of overfishing are not just damaging
to the ocean ecosystem but to the world ecosystem
(biosphere) as well because many other ecosystems rely
on the services of the ocean ecosystem. Although shrimp
are a small organism, their contribution to the ocean
ecosystem is massive. They are at the bottom of the food
chain and funnel nutrients and resources to all the
organisms above them. The blue whale, a giant of the sea,
primarily feeds off krill and other small organisms. In one
mouthful, a blue whale can swallow up to 500 kilograms
of krill [24]. The population of shrimp, krill and other
shellfish are essential for the ocean ecosystem and should
be taken seriously.
However, the bioplastic we are concerned with
utilizes only the byproduct of shrimp and other shellfish.
Each year, 6 to 8 million tons of crab, shrimp and lobster
shell waste is produced [14]. The current rate of shellfish
consumption is large enough to allow this bioplastic to be
made without creating a risk of over-shrimping that would
negatively impact the sustainability of the shrimp
industry.
wine drinkers allergic to shellfish. They found that there
had been one documented case of anaphylactic reaction
due to ingestion of chitosan [27]. The study noted that the
FDA has given chitosan GRN (generally regarded as safe)
rating which companies consider safe to use. The results
of the study concluded that chitosan-based films used in
the winemaking process are safe for shrimp allergic
individuals [27].
Chitosan is currently on the market being used
in various products. Food products, plastics, make-up, and
wines continue to be produced using chitosan. Chitosan’s
abundance around the world in discarded shellfish, along
with its biodegradability and apparent nontoxicity to
humans, makes it an ideal compound for use today and in
the future.
THE FUTURE OF CHITOSAN
The ability to incorporate chitosan technology
into our current technology is what we are striving for as
the future of chitosan. The current information we have
about chitosan-based bioplastic proves that it could be an
environmentally conscious and economically friendly
alternative to the current plastics. An abrupt change in
manufacturing chitosan-based bioplastic is not feasible
because the amount of shellfish waste is not ready to
compete with the current rate of plastic production.
Instead, a moderate shift towards chitosan-based
bioplastic production would be more approachable
because chitosan is currently abundant and readily
available for commercial and mass production.
Approximately six million tons of crab, shrimp, and
lobster shells are dumped annually around the globe [14].
While the entire plastic production currently cannot be
replaced, a substantial amount of that can be chitosanbased bioplastic. The collection and extraction of
crustacean shells is an industry waiting for development.
The future growth for chitosan-based bioplastics
lies in consumer based products and food packaging. The
plastic’s properties can be easily manipulated into many
household staples such as plastic bags, diapers, and plastic
bottles. These products are in high demand and are not
going to be eliminated from everyday use any time soon.
With further innovation in production methods, we can
change the production and construction of many of these
products to more sustainable and economically helpful
ones. In terms of packaging, promising oxygen absorbing
polymers are at the forefront. This technology stands
unopposed in the effectiveness of preserving food and
stands to continually increase its commercial usage [11].
A rise in usage of this packaging can help preserve meats
and many other perishable foods, cutting down food
waste significantly.
While we know that chitosan-based bioplastics
Shellfish Allergies
Since chitosan is a byproduct of shellfish, we
must address the concern for how chitosan-based plastics
would affect shellfish allergies. According to researchers
at the Wyss Institute for Biologically Inspired
Engineering, the chitosan does not cause shrimp allergies
because the part of the shrimp that causes allergies is in
the musculature part and not the shell [14]. This
information has been confirmed by other studies that have
identified the main allergen in shellfish as tropomyosin,
the muscle protein of shellfish [25]. Numerous products
that contain some form of chitosan are currently on the
market, including makeup, water treatment, and
biomedical products [14]. The safety of chitosan was
tested by Brooke Army Medical Center in conjunction
with HemCon Medical Technologies. They tested the
allergic reaction to a latex free bandage that was made
from ChitoClear chitosan, a registered brand of chitosan
made from pink North Atlantic shrimp [26]. The chitosan
went through an extraction process using acid to destroy
any existing proteins such as tropomyosin, which is noted
as the protein in shellfish that causes the allergic reaction
[26]. The study concluded that the bandage was safe in
patients who were allergic to shellfish.
Another study that tested for allergic reactions to
chitosan was done using wines. Wine makers have been
using a chitosan-based product as a preservative in the
winemaking process due to its antimicrobial properties.
The study wanted to confirm the safety of chitosan for
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Ava Chong
can replace most everyday plastic objects, there is still
much more to learn about other types of chitosan-based
bioplastic products. Current trials are underway to explore
the vast potential that chitosan-based bioplastics have.
One of the newest possible applications of chitosan is the
large-scale manufacturing of 3D objects [19]. These
objects can range from small structures to synthetic body
parts. FDA approved and easily pliable, chitosan-based
plastic has the potential to play a large part in synthetic
body parts. The major advantage for using chitosan-based
bioplastics is the drastic decrease in cost for the
consumer. This can allow synthetic body parts to be more
accessible for a wider range of people [19].
Implantable medical devices are another
possibility for the future of chitosan-based bioplastics.
The current trials for implantable medical devices utilize
the Shrilk form of chitosan. Because chitosan and the
fibroin are both FDA approved, implantable forms of
Shrilk are being investigated [2]. These implantable
medical devices include antitumor, anticholesteremic,
antioxidant, antimicrobial, blood cholesterol control,
regenerative effects on bones and tissues, and nerve
regeneration technologies [28]. Chitosan has also been
used as a major component in some bandages because of
its property that allows for rapid blood clotting [28].
Much of the technology for chitosan-based
bioplastics already exists but is not yet implemented.
There may need to be an incentive from the government
to accelerate the utilization of chitosan technology. Many
industries rely on chemically filled plastics and are
unwilling to pay money to change their current ways.
Subsidies from the government would be most helpful as
they can eliminate the cost of changing production
methods. Government incentives like tax breaks could be
another way to promote the switch to producing chitosanbased bioplastics. Once there is a stable economic market
for chitosan, industries would no longer need government
subsidies. The use of chitosan would then be a sustainable
economic technology.
The change to chitosan-based plastics is feasible
and ultimately sustainable. With contributions from
scientists, the government, and aware consumers, we can
hope to see the change soon. The enlightened consumer
can contribute to this change by choosing sustainable
products and reusing materials they already have.
However, the most important thing an individual can do is
inform others about what is going on and explain the
benefits of chitosan-based bioplastics.
Chitosan has a place in our future. Chitosan
productions for plastics can be a sustainable industry that
will benefit the environmental, societal, and economic
needs of present and future generations. We hope that this
technology can change the way we live and impact our
world for the better.
SOURCES
[1] K. Flint. “Biodegradable Plastic: Its Promises and
Consequences.” Dartmouth Undergraduate Journal of
Science. 4.2.2013. Accessed 3.1.17.
http://dujs.dartmouth.edu/2013/03/biodegradable-plasticits-promises-and-consequences/#.WLnehDsrI2y
[2] “Shrilk Biodegradable Plastic.” Wyss Institute.
12.13.2011. Accessed 1.10.2017.
https://wyss.harvard.edu/technology/chitosan-bioplastic/
[3] L. Knight. “A brief history of plastics, natural and
synthetic.” BBC. 4.17.2014. Accessed 3.1.2017.
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ACKNOWLEDGEMENTS
This paper would not have come to fruition without
the support from our peers and teachers. Specifically, our
writing instructor and co-chair, Keely Bowers and Marade
Bergen who helped us with our writing and ideas.
We would also like to thank the support system of
friends that we currently have at the University of
Pittsburgh. It is not without the inspiration and
encouragement from the Swanson School of Engineering
would any of this be possible.
8