Plastic Pollution's Impact: Understanding The Most Vulnerable Environments

Plastic pollution is a pressing environmental issue that affects all ecosystems, from the oceans to the Antarctic tundra. It is caused by the rapid increase in plastic production, with plastic waste ending up in the environment, where it can persist for hundreds of years. The pollution is most visible in developing Asian and African nations, but it is a global problem that requires systemic change. Plastic pollution has serious impacts on wildlife, the environment, and human health, and contributes to the climate crisis. It is important to address plastic pollution through measures such as reducing plastic production, improving waste management, and encouraging the use of reusable products.

Oceans

Plastic pollution in the oceans has become a global crisis. Billions of pounds of plastic are found in swirling convergences that make up about 40% of the world's ocean surfaces. At current rates, plastic is expected to outweigh all the fish in the sea by 2050.

Plastic pollution in the ocean has a direct and deadly effect on wildlife. Thousands of seabirds, sea turtles, seals, and other marine mammals are killed each year after ingesting plastic or getting entangled in it. Nearly 700 endangered species, including Hawaiian monk seals and Pacific loggerhead sea turtles, eat and get caught in plastic litter. A recent study found that a quarter of fish at markets in California contained plastic in their guts, mostly in the form of plastic microfibers.

Plastic pollution in the ocean also has harmful consequences for human health. Microplastics have been found in drinking water, salt, beer, and the soil where we grow our vegetables. Plastic materials are carcinogenic and can affect the body's endocrine system, causing developmental, neurological, reproductive, and immune disorders. Another health hazard is posed by toxic contaminants that accumulate on the surface of plastics and are then transferred to humans through the consumption of seafood.

The majority of plastic pollution in the ocean is caused by littering. We use disposable plastic items such as food wrappings, plastic bags, razors, and bottles, and do not dispose of them properly, causing them to end up in waterways and eventually in the ocean. However, not all plastic waste in the ocean is due to littering; much of it is the product of improper manufacturing processes, and about 20% of the ocean's plastic pollution comes from industrial fishing.

The problem of plastic in the oceans is growing. The fossil fuel industry plans to increase plastic production by 40% over the next decade, which will result in more toxic air pollution and plastic in our oceans. It is difficult, if not impossible, to retrieve plastic waste once it has entered the ocean. Therefore, many scientists and conservationists advocate for improved waste management systems and recycling, better product design, and a reduction in the manufacturing of unnecessary single-use plastics to prevent plastic waste from entering rivers and seas in the first place.

Land

Plastic waste that is not recycled, incinerated, or disposed of in sealed landfills becomes an environmental pollutant. Landfills, where much of the plastic waste ends up, can take up to 1,000 years to degrade, leaching potentially toxic substances into the soil and water. Chlorinated plastic, for example, can release harmful chemicals into the surrounding soil and seep into groundwater, rivers, or other water sources, causing harm to the species that drink the water.

Microplastics, which are plastic particles smaller than 5mm, are a significant contributor to land pollution. They are released into the environment through various sources, including synthetic textiles, tyre abrasion, and the degradation of larger plastic items. These microplastics can be transported over long distances and have been detected in tap water, affecting human health.

Sewage is a significant distributor of microplastics, with 80-90% of plastic particles from sources such as garment fibres persisting in sewage sludge. When this sludge is applied to fields as fertiliser, thousands of tons of microplastics are introduced into the soil annually.

In addition to contaminating water sources, microplastics can interact with soil fauna and affect their health and soil functions. For example, the presence of microplastics can alter earthworm behaviour, impacting their fitness and soil conditions. Microplastics have also been linked to a decrease in species that live below the surface, such as mites, larvae, and other tiny creatures that maintain soil fertility.

The chemical effects of microplastics are particularly concerning. As plastic particles break down, they can release additives such as phthalates and Bisphenol A (BPA), which are known to disrupt the hormone systems of vertebrates and invertebrates. Nano-sized particles may also traverse cellular barriers and enter sensitive areas like the blood-brain barrier or the placenta, potentially causing behavioural changes and adverse health effects.

Freshwater

Plastic pollution is a pressing environmental issue, with the world struggling to deal with the ever-increasing production of disposable plastic products. While plastic pollution is most visible in developing nations in Asia and Africa, it is a global issue, with plastic having been found in every ecosystem on the planet, from the Antarctic tundra to tropical coral reefs.

Indeed, studies have confirmed the ingestion of microplastics by wild freshwater organisms, including fish in France and the USA, and freshwater birds in Canada. In addition, the chemical content of plastic particles is a particular concern in freshwater habitats. These chemicals, which are present due to the constituents or additives used to manufacture plastics, or because plastics adsorb contaminants present in water, can be toxic or disruptive to hormonal systems. Exposure to these chemicals has been shown to impair reproduction and development in freshwater species in laboratory studies.

The impact of plastic pollution on freshwater ecosystems is further compounded by the fact that it acts as a conveyor, enabling plastic waste to reach the oceans. While it is unclear how much plastic is retained within rivers, it is known that plastic waste in rivers contributes significantly to the plastic pollution in the oceans. For example, two studies estimated that between 1.15-2.41 and 0.21-4.38 million tonnes of plastic per year entered the oceans from land via river catchments.

Overall, while plastic pollution is a significant issue for freshwater ecosystems, it is important to acknowledge that it is just one of many threats facing these environments. Other pressing threats to freshwater ecosystems include loss of connectivity and flow reductions due to dams and other artificial barriers, over-abstraction of water for irrigation and other uses, and the impact of climate change.

Human health

Plastic pollution is a pressing environmental issue that affects all ecosystems and poses a significant threat to human health. While the full extent of the impact of plastic pollution on human health is yet to be fully understood, current evidence suggests that it has wide-ranging and severe effects.

Exposure to Plastic Pollution

Humans are exposed to plastic pollution through various pathways, including inhalation, ingestion, and direct skin contact. Plastic pollution has been found in the air, soil, and water, as well as in food and beverages. Microplastics, tiny plastic particles less than 5mm in size, have been detected in seafood, tap and bottled water, beer, salt, and other commonly consumed products. Humans are also exposed to plastic pollution through the use of plastic-based medical supplies and consumer products, as well as during the extraction, manufacture, transportation, and waste management of plastic materials.

Health Risks Associated with Plastic Pollution

The health risks associated with plastic pollution are diverse and can affect multiple systems in the human body. Here are some of the key health impacts that have been identified or are suspected:

• Cancer: Carcinogenic chemicals in plastic, such as those found in plastic products and fireproofing coatings, can leach into tap water and increase the risk of cancer. The production and refining of plastic also release carcinogenic substances into the air and water, posing a risk to nearby communities.
• Endocrine Disruption: Microplastics and toxic chemical additives in plastic have been linked to endocrine disruption, which can lead to reproductive, growth, and cognitive impairments. Endocrine-disrupting chemicals can interfere with hormone activity and have been associated with decreased reproductive health, infertility, obesity, and thyroid problems.
• Neurological and Developmental Issues: Exposure to plastic pollution has been linked to neurological and developmental issues, including neurodevelopmental impairment in children and liver and cell damage. Certain chemicals used in plastic production, such as fracking chemicals, are known to cause developmental toxicity and impairment of the nervous system.
• Cardiovascular and Respiratory Problems: Microplastics have been associated with an increased risk of cardiovascular diseases and respiratory complications. Additionally, air pollution from waste incineration and chemical exposure during plastic production can contribute to respiratory issues.
• Immune System Disorders: Plastic pollution has been implicated in immune system disorders, with certain chemicals known to have immunotoxic effects.
• Inflammatory and Autoimmune Conditions: Exposure to microplastics has been linked to inflammation and autoimmune conditions such as inflammatory bowel disease and rheumatoid arthritis.
• Diabetes: Endocrine-disrupting chemicals and microplastics have been associated with an increased risk of diabetes.
• Reproductive Health: Plastic pollution has been linked to decreased reproductive health, including impaired reproductive organ development and function in both men and women.
• Other Health Issues: Plastic pollution has also been associated with premature death, disability, weight gain, insulin resistance, and an increased risk of infectious diseases.

Addressing the Health Impact of Plastic Pollution

To address the health risks posed by plastic pollution, it is crucial to reduce the production, use, and disposal of plastic and associated toxic chemicals. This includes improving waste management practices, promoting recycling, and transitioning to a more sustainable and circular economy for plastics. Additionally, there is a need for further research to fully understand the complex health impacts of plastic pollution and to develop effective policies and interventions to mitigate these risks.

Climate change

Plastic pollution is a significant contributor to climate change. The production, refinement, and disposal of plastics emit vast amounts of greenhouse gases, exacerbating the warming of the planet.

The problem begins with the extraction and transportation of the fossil fuels used to create plastics. This process is carbon-intensive, releasing millions of metric tons of carbon dioxide into the atmosphere annually. Land clearance for oil extraction and pipeline construction further contributes to emissions, reducing the planet's capacity to remove carbon dioxide from the atmosphere.

Refining and manufacturing plastics is also a major source of greenhouse gases. The production of ethylene, a building block for polyethylene plastics, emitted between 184.3 and 213 million metric tons of carbon dioxide in 2015, comparable to the annual emissions of 45 million passenger vehicles. The projected expansion of carbon dioxide emissions from ethylene production between 2015 and 2030 further underscores the climate impact of plastic production.

The disposal of single-use plastics, which account for half of the over 300 million tons of plastic produced annually, poses another challenge. Landfills, where much of this waste ends up, account for more than 15% of methane emissions. The ever-growing mass of plastic waste in oceans, exemplified by the enormous floating patch in the Pacific twice the size of Texas, also has dire consequences.

Plastics break down into microplastics, which scatter across the globe, including the ocean depths. These microplastics are ingested by aquatic animals, including plankton, which historically play a crucial role in sequestering carbon dioxide. Evidence suggests that microplastics reduce the growth and photosynthetic efficiency of microalgae, potentially impairing plankton's ability to remove carbon dioxide from the atmosphere.

Additionally, incineration of plastic waste, though less common than landfilling, has a significant climate impact. Projections indicate that by 2050, greenhouse gas emissions from plastics incineration will soar, contributing to the overall climate crisis.

While recycling can help mitigate the climate impact of plastics by reducing greenhouse gas emissions, it is not a panacea. Only a small percentage of plastic is successfully recycled globally, and the process of recycling itself degrades the plastic, limiting its reuse potential.

Frequently asked questions