Design Life-Cycle

Danielle Koay

Shu Ren Zhang, Yi Ding

DES 40A

Professor Cogdell

Plackers Dental Floss: Raw Materials

Dental Floss is a critical product of use in many of our first-world oral hygiene routines. Flossing your teeth is something that dentists emphasize practicing time and time again in order to remove plaque, prevent cavities, and maintain the physical quality of your teeth. Most people floss their teeth one to two times a day. Plackers Dental Flossers—with single-use plastic handles—is a very popular dental floss product for its easy and convenient use. But do we realize what materials go into one single-use flosser? Plackers Dental Flossers are made up of non-recyclable raw materials. The short-lived life cycle of a single flosser is something that should be known to the public, with the significant, yet inevitable environmental impact it generates.

Originally, dental floss was made up of silk when it was first invented in the 19th century. Modern-day floss, such as Plackers Dental Flossers, have strong and thin fibers made up of nylon, with handles made of plastic.[6] Although Plackers Dental Flossers offer an eco-friendly version of their product, the original Micro Mint flavor is their best-seller, and is thus our main focus for the topic of raw materials. Manufactured in China with their patented Super Tuffloss®, it is likely that the product is produced with nylon and plastic, although their exact formula is not released anywhere.[2] Nylon is often found in everyday items such as clothing, ropes, and car tires, because this material is very durable. To make dental floss perform at its best, brands opt for nylon so that the floss is flexible, but supposedly unbreakable. The manufacturing process of nylon dental floss involves polymerizing nylon salt. Nylon salt is formed with adipic acid, hexamethylenediamine, and water.[4] Though adipic acid is found in beet juice, it is produced industrially through oxidation of the organic chemical compounds cyclohexanone and cyclohexanol with nitric acid. Hexamethylenediamine is produced from the hydrogenation of adiponitrile in ammonia. When adipic acid, hexamethylenediamine, and water are poured into a reaction vessel, nylon salt is created. This nylon salt is then poured out flat on a surface. It is then cut up into small chips, blended, melted, and pumped through spinnerets to form filaments. Once cooled, the filaments regather to form a yarn, and the ends combine to form floss. The floss is stretched repeatedly, to make the molecules longer and even stronger. As dental floss is used in consumers’ mouths, it must be hygienic. The floss is washed to get rid of any unwanted dirt, while being coated with a layer of wax that helps it pass through teeth more easily. Though undisclosed, the most common components to create the sweet, minty flavor of dental floss are acesulfame, saccharin, and artificial flavor. Some flosses use peppermint powder, which serves both as flavor and a mild disinfectant.[1] Once these are coated onto the nylon component, the dental floss is ready for assembly.

As for the plastic component of this product, the raw materials carbon, hydrogen, cellulose, coal, salt, and crude oil are used to be refined into ethane and propane. Carbon is removed from the atmosphere from carbon sequestration, which is direct air capture.[9] The most common and efficient way to acquire hydrogen is to react carbon monoxide with water, using steam. Cellulose is often extracted from either plant sources or agricultural waste. Coal is produced by mining. It is formed due to heat and pressure in dead plant matter over hundreds of millions of years. Salt is produced either through seawater evaporation, or through mining. Crude oil, a fossil fuel formed from organic material over millions of years, is extracted by drilling or pumping from the earth.

These raw materials are used to eventually become plastic. First, they are treated with high heat and converted into ethylene and propylene. These monomers are then combined with a catalyst to create a polymer “fluff”. This polymer is melted through an extruder, and forms a long cylinder when it cools.[5] After it is cut up into small pieces, it is ready to be melted with dye for color–green dye for Plackers’ Micro Mint product.[7] The plastic then molded into the Plackers floss handle. The dental floss is cut up into pieces about an inch long, and attached to the plastic handles. The outer packaging that holds all the Plackers is made of plastic as well. Apart from plastic, the packaging contains ink that is printed onto the surface of the packaging. To print ink onto packaging, the process of flexography is used. First, the packaging is in roll form that would later be cut and sectioned into individual packagings. These rolls are pulled through a heat plate machine, and the branding and images are printed onto the bags as the plates are rolled onto the roller.[3] The packaging is finally individually cut. The Plackers are packed into the plastic packaging in packs of 90 single-use flossers. Once sealed, they are put into boxes and are ready to be distributed and sold to distributors worldwide.

To transport their products from the factories, Plackers mainly use sea freight and land. Sea freight cargo shipment is used to transport their products overseas from China to worldwide. From China to the U.S. west coast, it takes approximately two to four weeks to arrive.[10] The products are shipped by being put in cardboard boxes before being put into the cargo ship container. The cargo ships use diesel combustion engines to run the ship. Cardboard is made of cellulose, which is made from specially grown trees. Once they reach their destination, they are sent by land through trains or trucks to be sent to their retail store, which requires gas. Consumers are now ready to buy and use Plackers from the shelves of their nearest retail store location.

Consumers who use Plackers Dental Flossers typically use each flosser only once before throwing them out, and it is also recommended by both the brand and dentists that they do so. Because of this, there is no reuse or maintenance involved with these flossers. Plackers advertise their product as easy and convenient, and customers tend to love them for on-the-go flossing and for children. Consumers use them once to twice a day per person, and average families of four would use at least 4 Plackers flossers per day. The most popular packs have either 90 or 150 flossers, and once they run out, consumers opt to buy them again. Because they are non-recyclable, non-reusable, and contain mostly plastic, Plackers tend to take up a lot of volume in landfills.

Plackers says that their products are usually not recyclable, due to their small size and mixed materials.[2] Most Plackers users simply toss their flossers in the trash anyways, because it is unsanitary to recycle once it is used. Plackers does offer an Ecochoice version of their flossers, which are made of recycled plastic. Nonetheless, these Ecochoice flossers would be tossed into the trash as well and eventually reach the landfill. The materials, nylon and mixed plastic, tend to take decades or more to decompose. Evidently, Plackers flossers’ raw materials for their use are very wasteful and have a negative impact on the environment.

Although the Plackers product itself is not reusable or recyclable, the packaging that it is placed in is recyclable. The process for recycling plastic is that it is sent to a facility where it is sorted with other similar plastic types. They are separated by different properties such as color, thickness, and density. Then, it is washed and cleaned. Washing involves removing anything that is not plastic, including labels, adhesives, food residue, and dirt. They then shred the plastics which helps to remove any last impurities, such as metals being extracted with magnets. The plastics are sorted even further. The plastics are separated again through air classification, where the plastics are fed into a wind tunnel. The thinner pieces of plastic float, while the thicker and bigger pieces stay at the bottom. Finally, they melt and crush the plastic to form plastic pellets where they could be remolded again into recycled products.[8] Though the Plackers Flossers themselves are not recyclable, at least the packaging they are put in is able to be made into a new product.

Plackers, though a very popular brand that is both well-known and widely used, utilizes non-recyclable materials and is a single-use product. Nylon and plastic are the two main components that go into making this product, but other substances such as flavoring add appeal to the product. Manufactured in China, Plackers reach their consumers through sea freight and trains into retail stores. Consumers typically use their Plackers Dental Flossers one time before throwing it out, which would soon enough reach the landfill; its life cycle is very short-lived. No part of the Plackers Dental Flosser could be reused or recycled again. Though a necessary product for dental hygiene, there is much that goes into single-use dental floss: from the extraction of raw materials, to when it ends up in the landfill, taking multiple decades to decompose.

Works Cited

[1] Dental floss Information on Dental Floss. SWICOFIL. (n.d.). <https://www.swicofil.com/consult/core-markets/medical/floss>.

[2] FAQs. Plackers. (2020, July 27). <https://www.plackers.com/flosser-faqs>.

[3] |, A. (2021, February 11). Printing techniques for poly mailers, plastic bags, Envelopes. Polypak Packaging. <https://www.polypak.com/best-printing-techniques-plastic-shipping-envelopes/>.

[4] Nylon Manufacturing. Nylon manufacturing. (n.d.). <http://www.feature-tec.com.sg/solution/nylon-manufacturing.html>.

[5] PLASTICSMarCom. (2021, June 16). How are plastics made? This Is Plastics. <https://thisisplastics.com/plastics-101/how-are-plastics-made/>.

[6] Stavrakis, Adrian K., et al. “Performance Evaluation of Dental Flosses Pre- and Post-Utilization.” MDPI, Multidisciplinary Digital Publishing Institute, 18 Feb. 2022. <https://www.mdpi.com/1996-1944/15/4/1522>.

[7] Tech: Plastic dyeing – the permanent solution and alternative to painting. Front Street Media. (2017, January 12). <https://frontstreet.media/2016/07/13/tech-plastic-dyeing-the-permanent-solution-and-alternative-to-painting/>. 

[8] The Complete Plastics Recycling Process. Recycle Track Systems. (2020, October 12). <https://www.rts.com/blog/the-complete-plastics-recycling-process-rts/>. 

[9] What is carbon sequestration? What is carbon sequestration? | U.S. Geological Survey. (n.d.). <https://www.usgs.gov/faqs/what-carbon-sequestration>.

[10] Yiqi Zhang & Yuan Chang & Changbo Wang & Jimmy C. H. Fung & Alexis K. H. Lau. (1970, January 1). Life‐Cycle Energy and environmental emissions of cargo ships. Journal of Industrial Ecology. <https://ideas.repec.org/a/bla/inecol/v26y2022i6p2057-2068.html>. 

Shu Ren Zheng

Yi Ding, Danielle Koay 

DES40A

Professor Cogdell

16 March 2023

Embodied Energy of Dental Floss Picks

Practicing good oral hygiene to keep the teeth clean is an important daily necessity for everyone. Beside using a toothbrush to brush the teeth, another important item that keeps our teeth clean are dental floss. In a nationally representative analysis, on average 30 percent of Americans floss their teeth daily (Sternberg 2019). With that many people using dental floss one might wonder how the product came to be and where it will end up after use. This research paper will go over the embodied energy that is produced from the life cycle of dental floss picks, in particular the Plackers Micro Mint Flosser, from manufacturing to distribution, while going over the raw materials, waste, and emission. 

The word energy can be described as the “ability to do work,” by utilizing the chemical or the physical resources to provide the heat or light in machinery (Energy costs 2021). And that energy is being used everywhere from drilling for fossil fuel to transportation of goods in trucks to the consumers. To understand the energy produced and required for dental floss picks we first need to understand the life cycle of it by breaking up the product into different parts. Each part has its own uniqueness and the required energy to obtain and produce the product that is known as dental floss picks. 

When asked to list the materials used to make dental floss, many will answer the string that is used to floss the teeth. Then with a dental floss pick, it is followed by the plastic that is attached to the string. Now what is the string that is used to floss the teeth made out of? Well, it is made out of nylon and for the Plackers brand it is made of a type of nylon called Super TufFloss® fibers that is said to be easily slid between teeth without the use of wax coating or Teflon that is harmful to the body (Plackers). Since nylon is not a raw material but instead derived from a natural material called crude oil which is a mixture of hydrocarbons in liquid phase found in natural underground reservoirs (Liberto 2022). As stated above the floss is made from nylons, and nylons are mostly made of crude oils which are non-renewable fossil fuels known as liquid petroleum that are found naturally in underground reservoirs of the Earth’s crust. To get these oils, workers will first use a machine called a steam injector. It acts like a giant hose by pumping the heated water to the oil reservoir that will then push through the reservoir to the oil production wells (Fossil Energy Study Guide) . On average the number of barrels of crude oil produced per day is about 11.254 millions and the amount of energy produced from the injector and the wells is about 12.69 kWh per gallon (U.S. Energy Information Administration). After extracting the crude oil it will be transported to factories over the United States, also mostly overseas to China in order to produce nylon in the form of sheets/filaments. Since the nylon fibers are produced in factories with heavy machineries it will result in high levels of energy produced from it. On average, it is said that the “estimated energy used/produced during nylon production is about 85 MJ per kilogram by using a mix of electricity of 5.5 MJ/kg…” (Accessing Energy Requirement). The process of making nylon is by taking the main material of reacting carbon based chemicals found in crude oil and other sub materials like coal. It will then be put through intensive chemical processing that results in stretchy/string type fiber filaments that will twist together by 2.5 to 3.5 twist per inch to create a much stronger strand that is seen in many dental flosses (Rick 2020). 

Another sub production process is adding the mint flavor to the nylon floss. Since we are putting/using the dental floss picks in our mouth, companies and the consumers don’t want the floss to taste like plastic. So to tackle this issue companies will flavor their dental floss floss products with mint flavor. There is no information on what type of raw materials/chemical is used in company’s dental floss like Plackers, but typically mint flavor comes from a key ingredient called menthol [Why is Mint Flavor Popular…]. Companies use chemical energy to extract the chemical compound in order to add the minty flavor that keeps the mouth feeling fresh after use. 

The second main material is the plastic that holds the nylon floss which forms into a pick-like shape. Just like nylon, plastic is made out of several natural raw materials found throughout the ground, plants, or air. Those raw materials consist of crude oil, cellulose, coal, natural gasses, and salt which all come together to form plastic (How plastic is made). The process of combining the raw materials into what is known as plastics is complex but straight forward. The raw materials are refined into propane and ethane that is treated with high heat known as cracking to transform the monomers into ethylene and propylene. The monomers are combined into a catalyst to form a new polymer, which is placed into an extruder where it melts and fed into a pipe will form a long tube as it cools, which is later cut into small pallets for distributions (How plastic is made). Manufacturing plastics in factories requires fair amounts of energy, and that energy is kinetic energy that is measured in MJ or in megajoules. On average in the United States it is said that producing one kilogram of plastic using the raw materials requires approximately 62-108 MJ of kinetic energy (Energy Costs 2021). Since producing one kilogram of plastic requires 62-108 Mg of kinetic energy, that mean

As for the transportation of the raw materials to the factories in order to produce plastic and nylon, I did not find the exact type of vehicle used. So instead I decided to include data for all types of transportations vehicles and the amount of energy used. The following are different types of vehicles and the energy used in megajoules(MJ) per ton to miles: rail by diesel ~0.37 MJ/ton-mile, ocean shipping carriers ~0.23 MJ/ton-mile, 35 ton diesel trucks ~1.37 Mj/ton-mile, 15 ton diesel truck ~2.19 MJ/ton-miles, and long haul aircraft ~9.49 Mj/ton-mile (Qarout 2017). 

With the two main materials covered, we can now go over the energy used during the manufacturing process. There is not an exact information on how companies like Plackers manufactures their dental floss picks due to companies keeping almost everything a secret. But instead we have general ideas and information on the manufacturing process thanks to a published patent about disposable floss picks. It is said that disposable dental floss picks are normally made from special injection plastic mold to shape the plastic region of the pick (Disposable Floss Pick and Method of Manufacture). There are many different kinds of injection molding machines, but on average a small to medium size injection molding machine tends to consume about 0.9 - 1.6 kWh per kilogram of plastic making (Rex Materials). With the plastic being molded into a pick-like shape, the next step is attaching the nylon string to the plastic pick. From the published patent it is said that to attach the nylon string to the plastic, many companies use a certain type of adhesives called hot melt that is FDA approved. To melt the hot melt it requires thermal energy and on average the melting point is around 79.4 °C, but some are much higher, which is between 149 °C to 288 °C (Fink 2014). 

After everything is assembled the dental floss picks will need to be packaged in bags for shipment. The Plackers brands are mostly packaged in plastic bags with a dimensions of 8 x 10 x 1.75 inches. The type of plastic bag they used has what's called sure-zip seal which is similar to ziploc bags. As stated above companies tend to keep their manufacturing and production process tight-lipped so there is no exact information on the energy used during the process. So instead I found what the energy used for an average manufacturing and packaging facility. The average facility is said to utilize approximately 95.1 kilowatt per hour of electricity per square foot annually (Newton 2022).  At the distribution stage the goods are mostly transported by either cargo boats or planes from overseas manufacturing. As for in-state manufacturing the goods are either transported by trains, trucks, or cars. As stated from above here is the energy produced from different types of vehicles: rail by diesel ~0.37 MJ/ton-mile, ocean shipping carriers ~0.23 MJ/ton-mile, 35 ton diesel trucks ~1.37 Mj/ton-mile, 15 ton diesel truck ~2.19 MJ/ton-miles, and long haul aircraft ~9.49 Mj/ton-mile (Qarout 2017). 

After using the dental floss pick, where will it go? Does it get recycled or does it get thrown away and end up in the landfill? Well according to the Plackers, the Micro Mint Flosser dental floss picks are non-renewable/non-recyclable and must be disposed of after one time use. Therefore the dental floss picks will end up in the landfill as plastic waste. In 2018, it is estimated that landfills received 27 tons of plastic, which is about 18.5 percent of all of the municipal solid waste landfilled (Environmental Protection Agency). Since plastic does not decompose it will sit there together with other waste products, producing vast amounts of C02 and methane gas in the air which is harmful to humans and to the planet. 

Conclusion

During the life cycle of dental pick it produces all kinds of energy. It first starts with the gathering of materials using heavy machineries. Which leads to the manufacturing process in factories by utilizing mechanical, thermal, or chemical energy. The transportation stage also uses different types of vehicles which require a high amount of energy to transport it. At the end of the life cycle of dental pick it will end up in the landfill and will be sitting there while producing energy and harmful gasses to us humans and the planet. 

Work cited page

Assessing Energy Requirements and Material Flows of Selective Laser. Accessed 20 Feb. 2023. http://utw10945.utweb.utexas.edu/Manuscripts/2010/2010-26-Telenko.pdf.

“Energy Costs.” North American Forest Foundation, 28 Apr. 2021, https://northamericanforestfoundation.org/energy-costs/#:~:text=Plastic%20is%20produced%20from%20crude,efficient%20of%20these%20three%20materials.

EPA, Environmental Protection Agency. Accessed 9, Mar. 2023, Ahttps://www.epa.gov/facts-and-figures-about-materials-waste-and-recycling/plastics-material-specific-data.

“FAQs.” Plackers, 27 July 2020, https://www.plackers.com/flosser-faqs.

Fossil Energy Study Guide: Oil. Accessed 18 Feb. 2023. https://www.energy.gov/sites/prod/files/2013/04/f0/HS_Oil_Studyguide_draft2.pdf.

“Frequently Asked Questions (Faqs) - U.S. Energy Information Administration (EIA).” Frequently Asked Questions (FAQs) - U.S. Energy Information Administration (EIA). Accessed 20 Feb. 2023, https://www.eia.gov/tools/faqs/faq.php?id=667&t=6#:~:text=The%20annual%20average%20number%20of,power%20producers%20in%202021%20were%3A&text=Coal%E2%80%930.89%20kWh%2Fpound,Petroleum%20liquids%E2%80%9312.69%20kWh%2Fgallon.

Fink, Johannes Karl. High Performance Polymers. Elsevier, 2014.

Group, Parkcrest Dental. “Why Is Mint Flavor Popular in Dental Care Products?” Dentist in Springfield, Missouri, 16 June 2021, https://parkcrestdental.com/blog/faq/why-is-mint-flavor-so-popular-in-dental-care-products/#:~:text=This%20is%20because%20of%20one,which%20feels%20cool%20and%20refreshing.

“How Plastics Are Made • Plastics Europe.” Plastics Europe, 3 May 2022, https://plasticseurope.org/plastics-explained/how-plastics-are-made/#:~:text=Plastics%20are%20derived%20from%20natural,oil%20in%20an%20oil%20refinery.

Newton, Emily. “Energy Consumption in the Packaging Industry Impacts Sustainability Efforts.” Energy Central, Energy Central, 14 Dec. 2022, https://energycentral.com/c/ec/energy-consumption-packaging-industry-impacts-sustainability-efforts#:~:text=Although%20usage%20varies%20depending%20on,electricity%20per%20square%20foot%20annually.

Qarout, Layla. “Reducing the Environmental Impacts of Building Materials: Embodied Energy Analysis of a High-performance Building.” figure 36, (2017).

Rex Materials’ TCS. Accessed 10, Mar. 2023. https://www.rexmaterials.com/activek_apps/rmg/assets/tcs/System%20Design%20-%20TCS.pdf. 

Sternberg, Steve. How Many Americans Floss Their Teeth? - US News & World Report. Accessed 20. Feb. 2023. https://www.usnews.com/news/articles/2016-05-02/how-many-americans-floss-their-teeth. 

“US5246021A - Disposable Floss Pick and Method of Manufacture.” Google Patents, Google. Accessed 20. Feb. 2023, https://patents.google.com/patent/US5246021A/en. 

“U.S. Energy Information Administration - EIA - Independent Statistics and Analysis.” What Is Energy? Explained - U.S. Energy Information Administration (EIA) Accessed 20, Feb. 2023, https://www.eia.gov/energyexplained/what-is-energy/.

Wizard. “How Is Floss Made and What Is It Made of?” Dr. Rick Dentistry, 29 Apr. 2020, https://drrickdentistry.com/2016/09/01/how-is-floss-made-and-what-is-it-made-of/.

Yi Ding

Danielle Koay

Shu Renzheng

DES 40A

Professor Cogdell

TA Justin Marsh

Dental Floss Life Cycle  

Introduction

People today may explore deeply what interests them. For example, technology enthusiasts know the performance, specifications, production process, and other parameters of mobile phones, computers, and graphics cards. Fashion bloggers have sufficient knowledge of the color components of cosmetics, clothing materials, matching styles, etc. But for those products that appear in the corners of life and often inadvertently intervene in people's lives, people often have no concept of them or generalize them with a few broad words. But underneath these inconspicuous disguises, you may be surprised at how huge the industrial chain, and emissions are hidden behind it.

Dental floss is one such unassuming "plastic" piece. It's everywhere, in every bathroom, and in people's bags. People use it to clean food debris between teeth and discard it quickly. Such a short process that people may not even recall is repeated in many people for 24 hours, 365 days, and never stops.

It's evident that the main focus of this paper is not discussing the material of making dental floss, but knowing the background of its raw materials is still helpful for learning the waste and emission of dental floss.

Raw Materials 

There are two significant materials during the manufacturing process of dental floss: plastic and nylon. The type of plastic and nylon vary according to the brand and any particular use. P.E. (Polyethylene) and Nylon are polymer materials that follow the general manufacturing logic of making "plastic." However, they still vary according to the raw materials and specific processing technology.

Although Plackers didn't point out the actual name of the material they use, the official reply on Amazon still revealed that, except for one specific type of floss, the rest of Plackers' products all use "Ultra-High-Molecular-Weight-Polyethylene."

P.E. (Polyethylene) is what we usually call "Plastic," the plastic frame and packing bag both use P.E. and raw material, while the thread people use for cleaning is made of nylon fiber.

The polymerization of ethylene gas becomes polyethylene. According to the manufacturing techniques, different catalysts, and design purposes, some common P.E.s are sorted as follows: 

low-density polyethylene (LDPE)

high-density polyethylene (HDPE)

linear low-density polyethylene (LLDPE)

very low-density polyethylene (VLDPE)

The PE for packing bags usually belongs to LDPE, while the P.E. made for the floss frame is made of HDPE.

Manufacturing

For manufacturing raw materials making P.E., except recycling, the broadest method people use is heating oil and extracting naphtha. By refining naphtha, people can gain ethylene, the raw material for making P.E. Unfortunately, this procedure releases massive GHG.

The thermoplastic property of P.E. allows the manufacturing process uses thermal processing. This property points out another type of emission: gas release during thermal processing. The manufacturing process requires plastic to become hot enough to pass through the machine like an injection molding machine. As a result, it's inevitable to release gases. While heating, the P.E. will release gases, including acids, esters, peroxides, carbon monoxide, carbon dioxide, and other molecules. Ideally, burning pure P.E. only releases water and carbon hydroxide. Still, unfortunately, most plastic we are using right now is not pure P.E. Different chemical ingredients are added to provide P.E. with advanced properties. Therefore, heating and burning impure P.E. will release poisonous gases and damage the environment. 

It's a pity that we have no access to detailed data on the waste and emissions during the manufacturing of dental floss. But we still get some data about the emission related to the whole plastic industry. According to the data mentioned by OCED, in "Plastic leakage and greenhouse gas emissions are increasing," "In 2019, plastics generated 1.8 billion tons of greenhouse gas (GHG) emissions – 3.4% of global emissions – with 90% of these emissions coming from their production and conversion from fossil fuels." 

Many people assume that factories are the place that only releases waste and emissions. But, in fact, the life cycle of dental floss during the transportation phase also contributes to massive emissions.

Transportation

From the official description of Plackers, the Plackers brand dental flosses are made in China. Several transportation procedures are inevitable to deliver the floss from the factory in China to markets worldwide. For example, shipping to the U.S. requires transporting the product from the port in China first. After the products arrive in the U.S., we need those heavy-load trucks to send the cargo to the markets. Dental floss is everywhere, which means these trucks have to drive around. The same situation happens again. That's not possible for us the track where trucks deliver the dental floss, but what we can get to know is the general emission during the transportation. 

EPA, The United States Environmental Protection Agency showed two charts in "Fast Facts on Transportation Greenhouse Gas Emissions," namely 2020 U.S. GHG Emission by Sector and 2020 U.S. Transportation Sector GHG Emission by Source. Among them, emissions from transportation accounted for 27% of total emissions, while pollution from Medium and Heavy Duty Trucks accounted for 26% of total transport emissions. In other words, emissions from Medium and Heavy Duty Trucks account for 7% of the total U.S. emissions in 2020. Of course, this is not the emissions of the Plackers dental floss during transportation. Still, there is no doubt that in the life cycles of Plackers dental floss, the emissions generated by transportation account for a hefty proportion.

Disposal

Unlike most plastic products being collected, sorted, and recycled, dental floss seems not to follow these rules. We need to pay attention to the waste generated when these flosses are used. Hundreds of millions of dental floss are used and then discarded. Compared with reducing and controlling emissions through standardized production of raw materials, these wastes at the bottom of the life cycle are more challenging to handle and recycle properly.

The first consideration is quarantine and public health. "The Dental Solid Waste Management in Different Categories of Dental Laboratories in Abha City, Saudi Arabia." by Haralur, Satheesh B discussing treatments towards dental waste. The team mainly discussed and examined the different treatments for dental wastes attached to saliva and blood—the level of bacterial infection and infectious viruses. The whole research pointed out a severe idea that dental waste requires to be treated seriously. Dental floss fulfills all the critical points, like being attached to blood and saliva, and it has the threat to infest bacteria and viruses. So, dental floss requires to have some special treatment instead of being recycled. 

Many other reasons also prevent dental floss from being recycled. From the recycling perspective: It's small, massive in numbers, doesn't have a fixed using background, and appears almost everywhere, with low recycle value and lack of sorting. These points direct the final phase of dental floss: landfill or incineration. Dental floss transforms into harmful waste, is released into the atmosphere, or leaks into underground water.

From the user perspective:  The high frequency of dental floss use, highly regular and repetitive behaviors, and low cost have created a tremendous amount of dental floss used. Reducing the amount of dental floss in the final user phase is impossible. However, it's a necessity for most people. 

Suggestions

If you ask me if there are any options to manage or improve the treatment of dental floss in the users' phase, it's hard. Biodegradable plastic might replace the current non-degradable, but the cost might be problematic. In China, lot's of people prefer to use bamboo toothpicks. From the structure and functions, the toothpick is worse than dental floss because it may damage the gums. But its raw material, bamboo, is much more eco-friendly than Plastic materials. As a bio-material, bamboo can degrade quickly without causing any pollution. Also, bamboo grows fast. From farming to use only takes 3-5 years. 

The most significant improvement of the bamboo-based product is to become independent from oil. Don't use oil means we don't have to spend massive energy to heat, no more GHG are released, and bamboo can also consume carbon dioxide. 

So, combining bamboo as raw material to make thread and frame is a better direction. The bamboo base dental floss is already selling on Amazon, but it costs much more than plastic. But I am still looking forward to the bamboo-based dental floss replacing the plastic and nylon version in the future.

Through in-depth understanding and research on dental floss, behind this humble but ubiquitous little “plastic” piece, a complex production and technological background is hidden. Yet, at the same time, it is also recognized that the problem of waste and discharge of dental floss is ultimately attributed to the recycling of the disposal organization and us as the dental floss user.

Bibliography

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