Originally posted on EcoGeneration.org on 12 December 2022
Plastic is everywhere. You already know that. But what you may not know is how the chemicals and compounds in plastics affect everything from our water, food web, and all ecology in between. Let’s dive into what plastic is made of, and how it pollutes our waters and affects living things.
How it’s Made To understand the harms of plastic we need to start at the beginning. Oil and natural gas are extracted and refined into short-molecular chemicals (monomers) which are then linked together into long polymer chains. Once these chains are created the hot liquid plastic is cooled and cut into pellets to be melted down by manufacturers to produce plastic products.
But plastic isn’t simply made from oil and gas, though that is a large majority of it. These fossil fuels are mixed with various chemicals and materials which are referred to as additives. These additives range from stabilizers to slow or stop degradation, to plasticizers to make the plastic more flexible. Where does the water pollution start? The contamination of water begins with the extraction of crude oil. One liter of oil can contaminate one million liters of water. But the devastation goes further. Oil creates a thin layer over the surface of the water that stops oxygen from getting to the plants and animals that make the water their home. Sadly, a lot more than 1 liter is being lost in the sea. An estimated 1.3 million metric tons of oil are released into the sea every year. This oil damages vital ecosystems, contaminates drinking water, and causes terrible consequences for animals who encounter it.
Pollution in Production
We now turn to how plastics can pollute water during the production process. For the most part, the pollution during the manufacturing stage is air pollution. The heating of chemicals releases them into the air and can cause major issues for human health. However, it’s not uncommon for factories to “leak” microplastic pellets and chemicals into local water sources. One of these chemicals is Polycyclic Aromatic Hydrocarbons (PAHs). This class of chemicals occurs naturally in crude oil and gas. When released into water it can cause impairment to a variety of creatures, like fish, by disrupting their endocrine system - the system that uses hormones to regulate many functions in the body.
The biggest plastic pollution to water though is actually after the product has been used and disposed of. Often the plastic is not recycled or disposed of properly, as many of you have read about in some of my previous articles (The Brace for Impact Series), and it ends up in the environment where the most leaching of chemicals occur. These chemicals include Phthalates, an additive that can disrupt the hormone system and Bisphenol A, also an additive, actually disrupts the hormone systems of both vertebrates and invertebrates. Heavy metals like arsenic (As), Cadmium (Cd), Chromium (Cr), and Lead (Pb) also leach from plastics as they degrade in water. These heavy metals, if consumed by humans, can cause chronic toxicity, liver/kidney/intestinal damage, anemia, and even cancer. In fish it can cause deformities and mortality. Plants exposed to these heavy metals can have difficulty growing, inhibit photosynthesis, and ultimately causing mass plant dieoffs.
Flame retardants are commonly added to plastic, for obvious reasons. However, it’s found that Chlorinated Organophosphate (Tris), a flame-retardant chemical, is not staying in the products it is added to. A study found that between 1% - 4% is leaching into waterways. That’s more than a million pounds in the U.S each year. This causes the death of fish, feeds algae terrible blooms, changes the chemistry of soil, and can help the spread of invasive plants.
Polyethylene terephthalate (PET) is a very common additive and is often advertised as safe. But if we’ve learned anything from plastic marketing, you have to dig a little deeper to find the truth. And the truth is, phthalates cause endocrine and reproductive disruptions. And because PET can oxidize, it’s easy for it to leach into the water. The Harmful Attraction to Plastics Not only do plastics contain chemicals, scientists now know that they are actually attracting additional chemicals from the environment. According to a recent study, plastic debris in our oceans continues to absorb organic pollutants for months after they enter the water. Research by Chelsea Rochman, a graduate student at San Diego State University, showed plastics sitting in the water for several months contained more than 50 persistent organic pollutants. Among those pollutants were polycyclic aromatic hydrocarbons and polychlorinated biphenyls. The process by which these chemicals attach to plastics is called the adsorption process. This is when a chemical travels from a gas or liquid phase and forms a superficial monomolecular layer on the piece of plastic.
Impact on the Food Web
Though we’ve talked a little bit about the effects of these plastic chemicals on living creatures, it bears repeating and diving deeper to see the true effects on the food web as a whole. The chemicals leaching into the water can greatly affect the reproductive systems of animals, causing lower birth rates. This directly affects both that animal’s prey and its predator. The chemicals can also affect the growth of plants and even cause plant death which then creates scarcity for those animals that rely on it as food. Finally, we can’t forget that we are part of this dynamic and intricate food web. We eat plants and animals that rely on water and its resources. Chemicals easily make their way up the food chain to you and I.
What Can We Do 1. Advocate for the government to keep manufacturers honest and responsible for the chemicals they expose nature and all living beings to. Learn who your elected officials are and how to write an effective letter on our website. 2. Tell the top 10 plastic polluters where you stand on this issue. Get the list. 3. Make changes in your life to avoid or reduce single-use plastics whenever possible. Need help getting started? Check out our trash audit printable. 4. Clean up litter wherever you find it. Litter easily makes its way into all bodies of water. 5. Spread the word about plastic pollution and how others can make a difference.
Jenna is the founder of Official Trash Pirates, an organization that teaches children and their families about the effects of litter and climate change on our world. She hopes to get people of all ages involved in solving the litter crisis and empowering young people to make a difference in their community. Beyond her work with Trash Pirates, she is the mother of an eight-year-old boy and wife of an active-duty Air Force service member.