How the Process of Making Plastic is as Harmful as Plastic Waste
The surprising effects it has on our health and environment
Nowadays we constantly hear about how bad plastic is for the environment and the ways we can reduce the amount of plastic that ends up in landfills and our oceans. You've probably seen photos of plastic trash on beaches or plastic hurting wildlife, but waste isn't the only problem with plastic. The materials for plastic have to be drilled out of the ground, cleaned and processed, and melted into different products, all of which have their own harmful environmental and health effects (hello climate change!). That's why we took a deep-dive into the plastic-making process to help you better understand it's negative impacts on us and the planet. Keep reading if you want to be extra motivated to limit plastics in your life!
What is Plastic?
Plastic is a group of materials that are made out of organic and synthetic materials and are classified as polymers, a group of different combined atoms (2). Think of it like making a chain of paper clips to make a necklace or a paper clip garland! In order to make these polymers, raw materials are used such as cellulose, coal, natural gas, salt, and most commonly crude oil (3). And the reason plastic is so highly used is because it has the ability to be molded or shaped into virtually any form when heat or pressure is added, which is where the word plasticity comes from. Some other properties of plastic are low electrical conductivity, transparency, and toughness (4). And if plastic alone is not good enough for a specific product or purpose, the properties can be modified with different fillers, colors, foaming agents, and other modifiers creating really unique plastic products (3). Common additives are flame retardants which reduce flammability, phthalates which make plastic more pliable, and heavy metals, like lead and cadmium, which are stabilizers and add pigments. All of these additives have some level of health concern and when added to plastics increases the products toxicity (5). Other chemicals, like BPA, are used to manufacture certain types of plastics and the residual amounts of these chemicals later leach from the plastics during use. These additives and other chemicals are a big reason why there is such a push for individuals to reduce their plastic use because it could be directly affecting their health (5).
The Life-cycle of Plastic
A better understanding of how plastic is actually made is key to understanding why it's so problematic. Each step in the plastic making process has its own environmental and health impacts.
1. Extraction and Transportation
The first step to creating plastic is to extract the raw materials, which are most commonly crude oil and natural gas. Crude oil is found deep in underground reservoirs where large drills are used to extract it and this extraction can be done on land or at offshore drilling sites (6). Natural gas is also found in underground deposits, however, the extraction process is slightly different and uses a process called hydraulic fracturing. Hydraulic fracturing or fracking is when high pressure streams of water, chemicals, and sand are shot through rock breaking it open and releasing pockets of natural gas that are then captured (12). Once the oil and natural gas is extracted it needs to be transported to facilities where it can be further refined and processed into different materials. For the transportation, pipelines, ships, and trucks are used which all have high risks for leaks and spills that could cause further environmental damage and health concerns. And often the drilling sites and the refining facilities are in different countries which increases the amount of travel and therefore the emissions produced during transportation (7).
In this phase of making plastic there are a lot of potential health issues including cancer, liver damage, autoimmune disorders, allergies, respiratory issues, and reproductive and developmental issues (8,9,14). These issues come from the emissions of the machinery used to extract and transport the raw materials as well as the chemicals used to extract the oil and natural gas. Chemicals like benzene, other dangerous VOC's, and another 170+ toxic chemicals used in fracking can be emitted into the air or local waterways making risk of exposure extremely high (14). And along with health issues, there are a myriad of environmental issues including water contamination, poor air quality, oil spills, micro earthquakes, habitat destruction, and massive amounts of carbon dioxide emitted into the atmosphere (8,9,12,14). Some estimates show that 9.5-10.5 megatons of carbon dioxide per year is emitted due to the extraction and transportation of natural gas in the US for plastic production (7). That is a lot of carbon dioxide and subsequent climate change impacts for just one phase of plastics life-cycle!
After the crude oil and natural gas is transported to a refining facility, they need to be processed and rid of impurities like sand, sulfur, and other materials that might have been released during extraction (6). For crude oil this is done by heating the oil to a high temperature and then sending it to a distillation tower. In this tower the heavy oil is separated into lighter components called fractions (10). Some of these fractions include gasoline, kerosene, gas oil, heavy gas oil, and naphtha which is a crucial component to making large amounts of plastic (7). For natural gas a similar process is done, however, instead of immediately going into a distillation tower the gas is cooled in a Natural Gas Liquid Separator where products like ethane, propane, NGL, and natural gasoline are separated out (7,13). Next the naphtha and the natural gas products are further broken down into lighter components so they are easier to use. This method is called "cracking" and it can be done by using high heat and pressure which is known as steam cracking or by using catalysts to change the composition of the material known as catalyst cracking (10,11). The cracking process yields lighter monomers that are the building blocks of plastic and the most common ones are ethylene, propylene, butylene, benzene, toluene, and xylene (10).
To be able to transform the raw materials into the building blocks of plastic takes a tremendous amount of energy that most often comes from the burning of fossil fuels. At this point in the plastics life cycle, steam cracking accounts for most of the emissions made because it requires so much energy to heat up the materials as well as put them under extreme pressure. Along with the emissions from the amount of fossil fuels burned for energy, there are a lot of other carcinogens and highly toxic substances released into the air during refining and manufacturing. Workers in these plants, and people living in local and downstream communities are at higher risk of negative health impacts. Some of the documented effects of being exposed to such chemicals are impairment of the nervous system, reproductive and developmental problems, cancer, leukemia, and genetic impacts like low birth weight (7,14). The majority of US ethane cracker plants are located near communities that are low-income and communities of color, further contributing to environmental injustice.
3. Production and Consumer Use
Once the monomers are created from the refining and distillation process, they need to be converted into polymers. This process is known as polymerization and it is where the monomers are chemically linked together, which then creates a thick substance called resin. If we took the gaseous monomer ethylene and subjected it to heat, pressure, and a certain catalyst the monomers would join together creating the resin polyethylene, the most common form of plastic (10). Once the polymers are created they are sent through an extruder to create long tubes where they are then cut into small plastic pellets for easy transport to production facilities. These facilities will melt the pellets and mix in additives of their choice to create the desired product for consumer use (10).
During consumer use is when most of us are likely to come into contact with a lot of the additives put in plastic like BPA, phthalates, and flame retardants and so many more that can increase our risk for health issues. We can be exposed through skin to skin contact, ingestion of substances stored in plastic, or even by accidentally consuming plastic, and by breathing in fumes that might come from plastic products or the burning of plastic. Being exposed to these toxic chemicals is associated with renal, cardiovascular, gastrointestinal, neurological, reproductive, and respiratory systems problems, as well as cancers, diabetes, and developmental toxicity (5,14).
Many studies have shown that the impact of plastic doesn't stop after it has been thrown away. Once thrown away, a piece of plastic can travel through many different paths. One path is recycling which involves collection, transportation, processing, and remanufacturing, which often costs much more than just using virgin materials. Because it is so inefficient and costly to recycle materials, only 9% of all plastic made since 1950 has actually been recycled. Other pathways include incineration which accounts for 12% of the total plastic waste, and then the rest of the plastic has been buried, littered on land, illegally burned, or dumped into the ocean (7).
One of the biggest issues with plastic waste is microplastics. On average about 8 million tonnes of plastic is dumped into the ocean each year and eventually it breaks down into microplastics which makes it very difficult to remove (1). Marine species are heavily impacted by microplastics because often they mistake the small piece of plastic for food and while the plastic sits in their body it leaches out chemicals harming their bodily functions. And along with marine animals, humans are also heavily affected by microplastics. Not only do we eat some marine animals that are contaminated but microplastics have been found in sediment, soil, and air. Microplastics have even made their way into our food and drinks, such as beer, tap water, and sea salt (5,15). Although research is still ongoing, some potential health effects that may be linked to concentrations of ingested microplastics are metabolic disruption, immune dysfunction, neurodegenerative diseases, and chronic inflammation, which can lead to cancer (16-18).
With all the benefits of plastic, there comes a dozen issues that need to be addressed. Plastic production isn't going to stop overnight but there are ways we can reduce our exposure and try to slow down plastic production in the future!
How to Limit Plastics in Your Life
By far the type of plastic that contributes the most to the waste-stream is packaging! Plastic packaging accounts for 40% of all plastic being produced and is highly problematic. Most plastic packaging is made for a single use and because of its thin and flexible nature it is extremely difficult to recycle. Because of this 40% of packaging is directly put in a landfill while 14% is incinerated, 14% is collected for recycling (however, only 2% actually gets recycled), and finally 32% follows other pathways like open dumping, open burning, or littered on land or in bodies of water (7). If there is anywhere in your life that you should try and cut down on plastic, it's here! Check out a few ways you can use less single use plastic!
- Try not to buy foods or other products that are individually wrapped within a larger piece of packaging. An example of this would be small pieces of candy that are individually wrapped within a larger plastic bag or snack packages of crackers or cookies that come in a larger plastic bag.
- If you can buy things in bulk bins that are usually wrapped in plastic, opt for the bulk option. Usually you will save money and not have to throw away a piece of plastic!
- If available, buy the option packaged in cardboard or glass, instead of plastic.
- Clean and reuse old food jars or invest in glass food storage so you don't have to buy plastic tupperware, which is less durable. Your food is less likely to come into contact with any harmful plastic chemical additives this way.
- Look for biodegradable or compostable packaging. Many companies are using more sustainable packaging. This is a great way to support companies who are making good choices for the environment.
- Look for retailers who provide reusable options or bring your own. Plastic bags, disposable utensils, water bottles, take out containers, coffee cups, and more are all great places to start.
Plastic is a highly damaging and toxic material at every stage of its life. Not only is it being littered and thrown into our oceans, but it's adding harmful chemicals and tons of carbon dioxide into the atmosphere everyday. If we want to protect our health and the longevity of our environment we need to reduce the amount of plastic being used and ultimately how much of it is being produced. If you can do your part to slow down the damages made from plastic we urge you to start now!
- Toxic Additives in Plastics: Hidden Hazards Linked to Common Plastic Products | | SCP/RAC - Regional Activity Centre for Sustainable Consumption and Production. (n.d.). Retrieved June 25, 2021, from http://www.cprac.org/en/news-archive/general/toxic-additives-in-plastics-hidden-hazards-linked-to-common-plastic-products
- Cordes, E. E., Jones, D. O. B., Schlacher, T. A., Amon, D. J., Bernardino, A. F., Brooke, S., Carney, R., DeLeo, D. M., Dunlop, K. M., Escobar-Briones, E. G., Gates, A. R., Génio, L., Gobin, J., Henry, L.-A., Herrera, S., Hoyt, S., Joye, M., Kark, S., Mestre, N. C., … Witte, U. (2016). Environmental Impacts of the Deep-Water Oil and Gas Industry: A Review to Guide Management Strategies. Frontiers in Environmental Science, 4. https://doi.org/10.3389/fenvs.2016.00058
- Johnston, J. E., Lim, E., & Roh, H. (2019). Impact of upstream oil extraction and environmental public health: A review of the evidence. The Science of the Total Environment, 657, 187–199. https://doi.org/10.1016/j.scitotenv.2018.11.483
- Campanale, C., Massarelli, C., Savino, I., Locaputo, V., & Uricchio, V. F. (2020). A Detailed Review Study on Potential Effects of Microplastics and Additives of Concern on Human Health. International Journal of Environmental Research and Public Health, 17(4). https://doi.org/10.3390/ijerph17041212