Environmental Impact of Plastic Waste

Plastic is a synthetic material used to produce a wide range of objects. The manufacturing process of plastic objects requires polymer materials and other petrochemicals sourced from fossil fuels, which damage the environment. The production, use, and disposal of plastic bags and packaging are examples of how our consumption contributes to the environmental impact of plastic waste.

Disposing such items, i.e., plastic bottles and food containers, creates environmental waste. Plastic waste is one of the most dangerous and bulky wastes in the environment. 

The demand for mass production grows as the population increases, increasing the output of plastic garbage. We produce about 400 million tons of plastic waste yearly⁹. To learn more facts about plastic pollution, read our article on facts about plastic pollution. 

However, how does plastic pollution affect the environment and society? 

Keep on reading, as this article examines the current waste management systems and discusses the various effects of plastic pollution on the ocean surface, soil, and human health. 

Plastic Waste Management Systems 

There are various ways people around the world handle their waste. Improper and careless handling of waste contributes to plastic pollution in the environment. These management systems are: 

Landfilling 

The most common waste management method is landfilling. A landfill is a designated open dump area. The majority of our waste materials go to landfills. However, landfilling is proving difficult in some countries because they need more space.

Related read: Environmental Impact of Landfills.

Incineration  

Apart from dumping waste in landfill, burning is another standard method. However, burning plastic is not a suitable way of disposing of it. Instead, it creates more environmental problems. It releases fumes that contain harmful gases and toxic soots that are dangerous to the environment's health. 

Recycling  

Recycling is the most notable and eco-friendly waste management method. It involves the mechanical reprocessing of plastic packaging, debris, and scraps into a new product instead of using raw materials to produce a new batch of packaging materials, water bottles, or many other types of plastic waste. As such, recycling means we can reuse old plastic items. 

Read more: What Happens to Our Plastic Waste?

How Does Plastic Waste Affect the Environment? 

Plastic pollution affects every aspect and area of the environment. As the human population increases, plastic waste increases, impacting animals, humans, and other living organisms. Here are some adverse effects of plastic pollution on the environment: 

Effects of Plastic Debris on the Marine Environment 

Plastic waste is one of the major contributors to marine pollution. Plastics in the marine environment¹⁰ degrade at a different rate than plastics in the terrestrial environment. Ocean plastics break down into smaller pieces, known as microplastics, at a slower rate. 

The plastic materials in marine environments break down through photo-oxidative processes. In contrast, plastics in land ecosystems break down through processes like thermal oxidation, photo-oxidative degradation, and biodegradation.

This degradation process affects the biota and faunal communities of the ocean. The materials used to produce plastics harm the environment when they degrade. 

Floating plastic waste also aids the transportation of alien species into several water sources, causing water pollution. These alien species disrupt the composition of an ocean's ecosystem. It can also lead to the extinction of marine life. 

Plastic and its Impact on Marine Life

Floating plastic debris significantly threatens marine organisms because they easily mistake it for food. Plastic floating on the ocean surface mixes with other food sources, and animals like sea turtles, seabirds, and mammals consume them, often mistaking them for actual food. Consuming plastic fills their stomachs, giving them a false sense of satisfaction. As a result, they can feel full, and it can prevent them from consuming actual food ending in starvation and death.

For example, a gray whale stranded on a West Seattle beach had large quantities of plastic bits in its stomach. They found plastic bags, duct tape, surgical gloves, and other plastic items in their intestines.

According to the United Nations, plastic pollution affects up to 817 marine species through entanglement and consumption. The amount of marine mammals and seabirds affected by plastic garbage keeps increasing because of the high levels of plastic production².

Also, the consumption of plastics causes internal injuries, lacerations, and infections. It reduces the ability to swim and is often responsible for the death of aquatic animals. Marine animals and organisms are at risk of getting entangled in plastic materials like plastic bags and nets. This can cause them to panic and injure themselves. Since 2012, plastic debris killed over 500 aquatic species through entanglement.

Sea Animals Affected by Plastic Debris in the Ocean 

Fish and sea birds are the common victims of plastic entanglements. Sea birds dive into the ocean to forage for food but often encounter plastic items on the ocean's surface. 

Plastic nets are their greatest enemy. One bird that is a victim of plastic entanglements is the gannet. The gannet is a plunge diver easily caught in nets and other plastic garbage. According to a study conducted between 1976 and 1985, in Helgoland, Germany, 29% of the dead gannets found died because they were entangled in plastic garbage⁷.

Like fish and other marine life, sea birds also mistake plastics for food. Sometimes, they consume plastic through their prey that has already consumed it. Their offspring can also ingest plastic through consumption through regurgitation feeding. 

This harms them in various ways. One of these ways is starvation, which leads to weight loss and possibly death. Consuming plastic fills them up, and they don't eat proper food because they think they are full. They don't eat for a long time, reducing their body mass.

This is dangerous because birds need to store fat for migration and reproduction. Plastic consumption causes the blockage of gastric enzyme secretion, low hormone levels, delayed ovulation, and reproductive problems. In addition, it leads to the birds' demise because of internal injuries and the blocked intestinal tract. 

The dangers of plastics in the ocean do not spare several fish species. A study documenting the amount of fish with ingested plastics showed that 386 marine fish species had consumed plastics. The study also showed a yearly increase in plastic consumption by fish. It increases by 2.4% annually. Plastic consumption by fish reduces fish activity rates and weakens their schooling behaviors⁴.

Effects of Plastic Waste on Human Health 

Plastic items like food packaging and plastic bottles contain harmful chemicals. Once we dispose of them as waste into the environment, they can also absorb other harmful pollutants. Interaction with this plastic waste can lead to health problems like cardiovascular disease, cancer, and reproductive health failure. 

Monomers and other plastic additives can replicate the effects of estrogen hormones in humans. Microplastics, the by-product of plastic degradation, are commonly found in the edible items humans consume. These plastic bits have infiltrated the food web. 

Research shows that a person consumes at least 50,000 microplastic bits yearly. We interact with plastics by eating food items and drinking water that contains tiny plastic pellets⁸. Also, we inhale the plastic particles in the air.

Plastic pollution in the ocean indirectly affects humans because of the sea animals we eat as food. Research shows that microplastics in the food chain might cause infertility⁶, obesity, and endocrine dysfunction. As mentioned earlier, it can mimic the functions of estrogen hormones, which are related to the cause of breast cancer.

Chemicals in Plastic Waste and Human Health

The threat to human health is majorly from the chemicals used for plastic production. These chemicals include bisphenol A (BPA) and plasticizers. We have limited information about the long-term effects of these toxic chemicals on the human body. Still, researchers discovered high levels of plastic chemicals in humans - especially in women and children¹. 

The research reports showed BPA, ethylparaben, methylparaben, and triclosan were above 90%. Exposure to plastic garbage can also lead to oxidative stress, inflammation, and DNA damage. Consuming microplastics can damage human cells, causing allergic reactions and cell death.

Another chemical used in plastic production is phthalates. Manufacturers use this additive in vinyl flooring, wall coverings, medical devices, pill coating, and cosmetic products. Disposing of these plastic products causes the phthalates chemical to leach into the environment. 

Researchers discovered that exposure of pregnant women and children to phthalates could lead to brain development impairment in children. It increases the risk of ADHD in children. Also, it has adverse effects on the male reproductive organs.

Effects of Plastic on Land   

Plastic pollution poses a great danger to soils and their fauna. Soil is essential for all food production and agricultural practices. Plastics enter the terrestrial environment through various means, like sewage sludge, littering, illegal dumping of plastics, fertilizer coating, and runoff. Soil is one of the largest holders of plastic waste. 

Microplastics, the result of plastic garbage patches breaking down in the environment, affect soil microorganisms, activating microbial activities and soil enzymes. Also, the soil absorbs the harmful chemicals leached by the plastic waste generated. Soil microorganisms further increase the reach of microplastics in the environment. Worms, mites, and bouncing bugs transport the waste through their burrowing and feeding activities. 

Furthermore, soil is the primary distributor of microplastics into the world's oceans and air. Runoff and erosion distribute the waste into rivers and other marine ecosystems. The plastics on the soil's surface become suspended in the air, and wind circulation transports them to various regions. Another reason plastic pollution is terrible for the terrestrial environment is that it can absorb multiple pollutants and heavy metals. It acts as a migration tool for invasive species. 

Effects of plastic pollution on soil nutrients 

Different plastics have different effects on soil microorganisms. Polyvinyl chloride (PVC) and polyethylene (PE) reduce the diversity of microbial organisms³. Low volumes of plastic in the soil reduce its microbial activities, while high plastic concentration increases it. It can also increase microbial communities, affecting the interaction between microorganisms and plants.

Polyhydroxyalkanoate-type polymer (PHBV) increases oligotrophic microorganisms and reduces the growth of vegetative organisms. Oligotrophic microorganisms are organisms that grow in nutritionally deficient areas. Plastic pollution in the soil facilitates microbial communities that can have unpredictable effects on the soil's properties and ecosystem.

Impact of plastic pollution on soil enzymes 

Soil enzymes have an essential role in the biological and biochemical soil processes. Agriculturalists use it to determine the fertility levels of soil in an area. It has a significant role in regulating the cycle of soil nutrients. Soil enzyme reactions to microplastics depend on the microplastics' type, concentration, size, and shape. It also depends on the soil environment and a host of other factors. 

The impact of plastic on soil enzymes goes two ways; it can activate enzyme activities or not affect enzyme activities. The impact also depends on their concentration levels. 

FDAse is a complex enzyme that contains phosphatase, cellulase, and lipase, and it is involved in cellulose and carbohydrate decomposition. Dehydrogenase is an enzyme that removes hydrogen molecules, especially in electric chain reactions of soil cell respiration. At the same time, urease is a protein that begins the hydrolysis of urea. Plastic pollution reduces the activities of the nutrients mentioned above.

Research has found that high volumes of polypropylene can activate the activities of FDAse and phenoloxidase, while polypropylene in low concentrations has zero effect. High volumes of polylactic acid (PLA), polybutylene succinate (PBS), polyhydroxybutyrate (PHB) plastics increase the activities of urease, phosphate, and catalase.

Impact of Plastic Pollution on Soil Microorganisms and Plants  

The effects of microplastics on soil microorganisms and plants vary according to the exposure period. They enrich the microbial communities in the soil and disrupt the interaction between plants and microorganisms. Microplastics also serve as ecological habitats for microorganisms, and the release of plasticizers affects their growth. 

Plastic pollution has a severe, toxic effect on plants. It delays and reduces seed germination, disrupts plant growth processes, and changes root properties. Also, it reduces plant biomass, delays and reduces harvest, and interferes with photosynthesis. 

Microplastics interfere with plant growth by attaching themselves to their roots and changing their properties. Changing the root's properties and disrupting the root's ability to absorb water and nutrients.

They can also harm plants by infiltrating the plant's body and changing the state of the cell membrane and intracellular molecules. This causes the affected plant to enter a state of oxidative stress. Pollutants from organic waste absorbed by microplastics and plastic chemicals also leach into the plant. 

Essential soil fauna like earthworms, mites, amoeba, and springtails also suffer damage from plastic pollution. They often feed on microplastics in the natural environment, reducing their soil population. It causes intestinal damage, immune disorders, and oxidative stress. Affected plants could also experience neurotoxicity, reduced growth and survival rates, and DNA damage.

Consuming microplastics disrupts the feeding habits of soil fauna. Microplastics in plants also disrupt the food chain. Any other living thing that consumes plants with microplastics is indirectly consuming plastic. They are at risk of experiencing health and cellular problems. 

Related read: 6 Facts About the Role of Soil Health in Climate Change Mitigation.

Contributes to Climate Change  

All stages in the life cycle of plastic products, from production to disposal, produce greenhouse gases. We do not recycle most of the plastic trash we produce. Records show that about 16% of the plastic debris we throw away is recycled⁵. The ones we don't recycle end up in landfills and several water sources. Sometimes, it's often directly present in the atmosphere.

It breaks down into smaller microplastics and releases carbon dioxide and methane. Research also shows that plastic affects the ability of microorganisms to absorb carbon dioxide and release oxygen. Plastic pollution in the world's oceans interrupts the ability of plankton, marine organisms, to grow, reproduce, and capture carbon.

Improper disposal of plastic also contributes to climate change. Burning plastics releases a lot of toxic chemicals into the atmosphere, increasing the rate of global warming. 

Proper disposal in a landfill also releases greenhouse gas emissions as the plastic breaks down. The gases from burning and degradation trap heat in the atmosphere, stopping it from escaping. Climate change catalyzes a series of environmental disasters like food scarcity and extreme weather. 

Conclusion  

Plastic is a versatile synthetic material used to produce a lot of objects we use in our everyday life. However, it is more dangerous to the environment. It is best if we reduce our plastic usage. We rely too much on it, using it to create excessive packaging and construction materials. Then, when we use these materials, we don’t throw them away correctly. 

We create plastic litter, which accumulates into plastic pollution. Landfills need to be handling plastic waste efficiently. This leads to public health problems and climate change. We need to reduce the plastic waste we produce. Instead of using plastic bags and containers, switch to zero-waste products, reusable bags, and food packaging items.