There’s more to plastic pollution than meets the eye
How plastic pollutes our water systems from Extraction to disposal.
Plastics are widely used in our society. They are convenient, cost-effective, and have many applications. Due to the extensive use, plastics are a major pollutant. They are hard to recycle and reuse, but they take several years to degrade and often end up in bodies of water.
We are aware that plastic pollution is a problem in our water systems and land. But this problem goes far beyond being an eyesore and harming animals that can confuse the plastic with food or get entangled into some plastic container.
Plastics contain harmful chemicals that leach into our water bodies.
Small pieces of plastic (or microplastics) are formed by plastic break down. Because of the extent of plastic pollution in our water sources, these microplastics are incorporated into our ecosystems. We consume them in our food and water.
A study from the University of Newcastle in Australia estimated the amount of microplastics consumed by humans. This study suggests that, on average, we consume 5 grams of microplastics per week. This amount depends on eating and drinking habits.
This isn’t a new problem either. Plastic pollution in oceans was first detected in the North Atlantic Ocean in the 1970s. Estimates from 2015 suggest that there are around 5-13 million metric tons of plastic waste in the world’s marine environment.
To make that number easier to digest, imagine that in the form of male elephants. We all have a general idea of how massive one elephant is, but did you know that one male elephant can weigh up to 7 metric tons? Although that is an impressive weight, matching the amount of plastic polluting the ocean would take around 1 million full-grown elephants.
Source: Kala Senathirajah and Thava Palanisami- The University of Newcastle, Australia
The life cycle of plastic
Plastic pollution begins long before a plastic bag or water bottle even reaches the ocean. To fully understand the extent of the damage plastic has on our aquatic ecosystems, we have to look at the product life cycle. That means observing pollutants from extraction to disposal.
Plastic manufacturing produces a significant amount of harmful chemicals, and most of these pollutants are released into the air. These toxic chemicals include methanol, acetone, and a large variety of organic compounds.
Let us look at the following example of the PET (a form of polyester) manufacturing pollution issues—the manufacturing of one 16 oz. PET bottle produces 100 times more harmful emissions to air and water than the manufacturing of a 16 oz. glass bottle.
Besides the toxic chemicals released during plastic manufacturing, their chemical toxicity depends on their chemical and physical properties such as particle size, shape, and polymer type. Chemicals are added to plastics as softeners, flame retardant agents, colorants, fragrances, and more. These chemicals improve performance, but this increases the harmful effects of plastic pollution in our environment.
Some plastic additives further decrease the decomposition of plastics. These additives are also toxic and end up contaminating our oceans as plastics enter the water systems.
With all of the additives and chemicals it takes to produce plastics, it is no wonder that these toxins can also leach from plastic containers when we eat or drink from them.
We are exposed to plastic products every day, and depending on where you live, the exposure can be greater. Plastics can leach chemicals if heated or scratched, and that certain levels of chemicals (present in plastic) such as BPA (Bisphenol A) are linked to cancer (BPA is a synthetic estrogen causing hormone disruption. This disruption is linked to breast cancer and brain development issues in the womb).
Example of Linear Production system and product life cycle - Image originally created by megcarney.com
Effects of plastic in water
Once we are done using a plastic Tupperware or throw out a plastic trash bag, as consumers, we don’t really know what happens to these items. If we recycle a plastic bottle, we don’t even know if it actually is being recycled. This disposal part of a plastics life cycle is often the one that we are most conscious of, but it is also one of the most detrimental.
Plastics create a physical and chemical impact to the aquatic environment when plastics are disposed of and end up in rivers, lakes, and oceans. Chemicals present in plastics can leach out and become part of the food chain. To make things worse, since plastics take a long time to degrade, the chemicals present in plastics have more time to leach into the aquatic environment.
Some of the harmful chemicals associated with plastic pollution in the aquatic environment include pesticides, metals such as zinc, cadmium, and aluminum, and hormone disruptors associated with a variety of health problems.
Plastic pollution in aquatic environments also causes animal entanglement, and smothering. As plastic degrades into smaller and smaller plastic pieces, it can be easily eaten by aquatic animals. This plastic ingestion by animals can cause animal death directly or indirectly by causing poor nutrition or dehydration. Animals are also affected by the harmful chemical these plastics contain.
Besides aquatic animals facing the consequences of plastic ingestion, there are consequences of ingesting the chemicals in plastics. Aquatic animals are exposed to chemical additives in plastic in different ways:
Direct ingestion (animal eating plastic)
Indirect ingestion (animal eating prey that consumed plastic)
Dermal exposure.
And in turn, we are exposed to these chemicals by the consumption of these animals.
How are chemicals in plastic leaching into our water?
While we are aware that the toxins in plastics each into our water, how does it happen?
In 2009, scientists from Harvard found BPA from plastic bottles leaching into humans. BPA, a chemical used to make plastics, found to leach from polycarbonate drinking bottles Into humans. This study showed an ⅔ increase in the BPA present in the participants' urine after one week of drinking water from BPA bottles.
Scientists have also investigated how chemicals in plastics leach into aquatic systems.
Chemical concentrations in some animals are related to the amount of plastic they ingested and the number of chemicals present in the plastic. It is believed that the presence of toxic chemicals in basking sharks and fin whales is related to microplastic ingestion.
There is evidence of chemical transference from plastic to aquatic organisms. One study shows an increased concentration of chemical accumulation in lugworms, a large marine worm, if they ingested plastic with the chemical adsorbed.
Results showed that lugworms had a higher concentration of toxic chemicals if they ingested the chemical on the plastic debris. On the other hand, the concentration of toxic chemicals was less if the lugworms ingested the chemical from contaminated sediment.
What can we do now?
Water pollution is a serious problem.
Plastic debris is found in almost all freshwater and marine environments. It is present near high populated areas, in the remote ocean, if you take a hike along a stream, and virtually anywhere on Earth that water touches.
With such a widespread problem, what can we do?
More studies about the effect of plastic and related chemicals are necessary, but measures are being taken to reduce plastic pollution. Some federal agencies, such as the EPA’s trash-free waters program, work towards preventing trash from entering waterways. This initiative combines public and private collaboration to help businesses reduce litter, packaging waste, and prevent plastic from ending up in the ocean. This is an excellent governmental strategy, but we can all do our part to reduce plastic waste.
As individuals, we can help reduce plastic waste by not using single-use plastic, recycling properly, reusing containers, and buying food in bulk. We can also help by joining clean-up events, staying informed, and spreading the word about harmful plastic effects on our environment and ourselves.
How have you been reducing your plastic use? Let us know in the comments below.