Over the past few years I have become more and more aware of the effects plastic pollution has had on our planet. This paper explores using fungi as an alternative to plastics for various products.
Plastics: Issues and Alternatives
The Past Present and Future of a Modern Material
Cassidy Brennan
Headlines blasting news about issues surrounding land and ocean pollution are the new normal these days, and they all center around the same substance: plastic. An article released this past summer stated: “We estimate that 8300 million metric tons (Mt) of virgin plastics have been produced to date. As of 2015, approximately 6300 Mt of plastic waste had been generated, around 9% of which had been recycled, 12% was incinerated, and 79% was accumulated in landfills or the natural environment. If current production and waste management trends continue, roughly 12,000 Mt of plastic waste will be in landfills or in the natural environment by 2050” (Geyer et al., 2017). Here we will describe what plastics are, and how we got to this point in history.
Plastics have an extensive history that begins long before what we would consider the modern material that is used in so many things. Plastic is made from polymers, which are defined as “a substance that has a molecular structure consisting chiefly or entirely of a large number of similar units bonded together”. Many polymers have been made of organic materials, especially in the past, but more recently synthetic polymers are what is used to create materials used in most everyday items. Not all things that you might believe to to be a synthetic material actually are, however. Rubber, first discovered in the 1700’s and utilized as a durable material in the 1800’s, is derived from a type of tropical tree. In 1907 the first synthetic plastic was made with an acid derived from coal tar, and from there, the plastic industry took off creating different kinds of materials for different applications. Throughout the early 1900’s, different chemical variations of polymers were used to create materials we know today: polystyrene (1929), polyester (1930), polyvinyl chloride (PVC), polythene (1933), and nylon (1935). Petrochemicals were what made these advances possible, as well as other chemicals such as chlorine (Knight, 2014). These are all still used today, as well as many other variations that have been added throughout the past decades. Plastic polymers are used to make anything from car and building parts, to clothing, containers, and cling wrap.
Synthetic polymers do not biodegrade, but do still break down into smaller and smaller pieces, that is if the material has an opportunity to break down at all and create what are called microplastics. Many plastic products are designed for single use applications and are discarded once they are no longer considered useful. The combination of the size of the Earth’s population as well as the planned obsolescence of materials means that landfills all over the world fill rapidly with straws, plastic coated cardboard and paper wrappers, “disposable” cutlery, broken plastic items that are not easily repaired, and so on. Not all items end up in landfills- garbage litters roadways and beaches, polluting habitats and waterways with unused junk. This may seem harmless (yet annoying) at surface value, but the issue goes much deeper. Microplastics are being eaten by microorganisms and bioaccumulating up the trophic levels, eventually ending up in the food we eat and in our own bodies. This discovery has led to studies that are investigating how chemicals are absorbed and released by plastics, and how they affect our bodies as well as those of other organisms. In an article published in the spring of 2017, contaminated table salt was a topic explored, and they had data on what types of plastics were found in the salt sampled in the study. According to their graph, the most common types of plastics are styrofoams and those used in packaging:
“In this study, we further investigated the presence of MPs [microplastics] by extracting particles from 17 different brands of salt originating from 8 countries over 4 continents. Density separation and visual identification were employed to initially isolate MP-like particles. Finally, all particles were analyzed by micro-Raman spectroscopy for their chemical composition.” (Karami et al, 2017)
(a) Pie chart of the chemical composition of the isolated particles from all salt samples and the corresponding proportion of different (b) plastic polymers and (c) pigments.
Thankfully there are alternative materials that businesses and consumers can utilize in place of plastic polymers. Consumers play a large part in what is designed and manufactured because of what economists call supply and demand. If consumers are supporting the companies that are designing and selling products that they want (ethically and practically), then there is more demand for those products. There are a wide variety of creative alternatives to plastic for almost every application. Some common replacements are in household products such as packaged groceries, cleaning supplies, and beauty/ hygiene products. Alternatives for these are as simple as buying less individually wrapped products and not using bags while grocery shopping, cleaning with simple homemade cleaners with baking soda and vinegar bases, and again buying less packaged hygiene products such as solid bars of soap. Along with reducing plastic consumerism, a reduction in consumption of goods in the broad sense is the best way to impact issues regarding global pollution and landfills. On a more global scale, companies all over are experimenting with materials that are alternative to plastic and have made some innovative discoveries. Plants can be used to create a plastic like polymer that is compostable, and there are even kinds on the market that are edible after use made from seaweed or corn (Matarani et al., 2017). Packaging is a different issue and one that has many plant based solutions as well as alternatives using recycled materials to keep plastics and usable paper out of landfills. One of the biggest breakthrough alternative materials that I have seen comes from an unsung hero: fungi.
In the movement towards sustainable packaging, the best so far has been seen using the mycelial mats from fungi to create custom shapes that compost easily and are made at an affordable price. Mycelium are “the mass of interwoven filamentous hyphae that forms especially the vegetative portion of the thallus of a fungus and is often submerged in another body (as of soil or organic matter or the tissues of a host)” and could also be described as the root of a mushroom (Ecovative Design, 2017). Ecovative design is one of many organizations that are experimenting and currently using fungi to make a sustainable product. Besides being home compostable as well as able to compost on an industrial level, they describe their products as “rapidly renewable” and “fine tunable to meet your needs” which make them an attractive alternative to plastic packaging. On their website Ecovative Design breaks down their process in an easy to understand way:
They receive agricultural waste purchased from regional farmers.
Clean the agricultural waste and introduce it to mycelium.
Then bag this mixture and let the mycelium grow for a few days. The mycelium sees the agricultural waste as food and reaches out to digest it, forming a matrix of white fibers along the way (mycelial mat).
Each particle is then coated in mycelium and we break it up into loose particles again.
Loose particles are put into a tool (in the shape of what they need) where the mycelium grows through and around the particles, forming a solid structure and filling any void space. They let this grow for a few days until it is solid, and then remove it from the tool.
Materials are dried to stop growth and prevent it from producing mushrooms or spores, and the final shaped product is ready. (Ecovative Design, 2017)
Other companies, such as Mycoworks, that are experimenting with fungi and mushrooms, are looking to create alternatives to leather. Leather alternatives would reduce the need of leather from agricultural livestock operations that require a very high energy input to produce very little product. Mycoworks describes their product as being cost competitive, eco friendly (as stated previously) as well as biodegradable, and as being “strong, flexible, and durable, just like conventional leathers”. One final example of the use of mushrooms and mycelium, is from the company Mycotech. They grow mycelium in a way similar to Ecovative Design, but they are creating building materials, and restructuring the way we think of architectural design. On their website they describe their thoughts on the importance of design, as well as some of the drawbacks of mushroom based materials:
“Mycelium-based materials offer significant ecological advantages on the one hand but comparably low structural strength on the other. When building with materials that are weak in tension and bending, good geometry is essential for maintaining equilibrium through contact only -that is, through compression. Funicular geometry has the advantage that stresses in it are very low. Development of engineered materials, such as concrete or steel, is largely focused on making these materials stronger, on increasing their allowable stress. However, achieving stability through geometry rather than through material strength opens up the possibility of using weak materials.” (Mycotech, 2017)
Through creativity, education, and experimentation, the global population has many opportunities to create alternatives to plastics that can benefit our economy and our planet. Thankfully, what has been described as a cultural “addiction” to the material, may be coming to an end. The next question is: Can we clean up the plastic pollution that already exists before there is irreversible damage to our environments and to ourselves? Thankfully, there are solutions in the works that may be the answer.
Sources
Ecovative Design. (n.d.). We Grow Materials. Retrieved March 3, 2018, from https://www.ecovativedesign.com/home
Geyer, R., Jambeck, J. R., & Law, K. L. (2017, July 01). Production, use, and fate of all plastics ever made. Retrieved March 3, 2018, from http://advances.sciencemag.org/content/3/7/e1700782
Karami, A., Golieskardi, A., Choo, C. K., Larat, V., Galloway, T. S., & Salamatinia, B. (2017, April 06). The presence of microplastics in commercial salts from different countries. Retrieved March 3, 2018, from https://www.nature.com/articles/srep46173#introduction
Knight, L. (2014, May 17). A brief history of plastics, natural and synthetic. Retrieved March 3, 2018, from http://www.bbc.com/news/magazine-27442625
Matarani, Z., K., & Davies;, E. (2017, November 23). Indonesian startup wages war on plastic with edible seaweed cups. Retrieved March 3, 2018, from https://www.reuters.com/article/us-indonesia-evoware/indonesian-startup-wages-war-on-plastic-with-edible-seaweed-cups-idUSKBN1DN0XA
Mycotech Homepage. (n.d.). Retrieved March 6, 2018, from https://www.mycote.ch/biobo
Mycoworks Homepage. (n.d.). Retrieved March 6, 2018, from https://www.mycoworks.com/
Comments
Post a Comment