Plastics are an almost inescapable part of modern lives, as they have so many differing uses. They are a diverse group of materials which are made from petrochemicals (Reisser et al, 2013), that are lightweight yet strong meaning they are durable and they are also relatively cheap to produce, therefore they are one of the most suitable materials to produce a wide range of products, from clothing to packaging and household items (Derraik, 2002).
However, despite their useful nature, plastics have become a big problem in the world’s oceans. Plastic pollution arises from single-use plastics, plastic pieces, fragments, pre-production pellets (nurdles) as well as micro and nano plastics. Single-use plastics are the biggest market for plastics within the EU, and as global demand rises, this is likely to increase, which would cause a greater impact on the environment.
Due to the fact that plastic production has increased by 20 times in the last 50 years (BIR, 2016), the amount of plastic waste has also increased. While plastic products do break down over time, they never fully biodegrade, therefore small plastic fragments are still left in the environment as the majority of plastic waste within the EU goes to landfill rather than being recycled.
This, coupled with container spillages of nurdles such as the one in Hong Kong in 2012, dropping 150 tonnes of pre-production pellets into the environment (Discovery, 2012), now means that plastic is found from the poles to the equator, on every shoreline and estuary as well as in the deepest ocean trenches (Gall and Thompson, 2015). Not only this, put persistent organic pollutants are also being found on the plastic debris, which also has detrimental impacts on the ocean environment (Holmes et al, 2012). This pollution is expected to have numerous negative socio-economic impacts (Mouat et al, 2010) as well as detrimental environmental impacts for people and other organisms (Monroe, 2014).
What are the impacts?
When plastics begin to break down in the water, a toxic chemical called bisphenol A (BPA) is released. This chemical, along with others are ingested by organisms in the water and as they are lipophilic, they attach to the animal’s adipose tissue. Once in their bodies, the toxins cannot leave, therefore causing a number of issues, such as intersex, growth defects and reproductive issues due to their disruption of the endocrine system (Independent, 2009). Mothers can pass toxicity down to their young when they are feeding in a phenomenon known as a toxic dump, which may hinder their viability.
Plastics have the ability to adsorb hydrophobic toxins such as persistent organic pollutants (POPs) to their surfaces at concentrations one million times that in seawater (Van et al, 2012). POPs, such as polychlorinated biphenyls (PCBs), are organic compounds that are resilient to environmental degradation therefore cannot be broken down through chemical, biological, and photolytic processes (Environmental Protection Agency, 2016). Due to this resistance, they can often bio accumulate and cause environmental issues.
Due to the fact that many organisms ingest plastics as they mistake it for food, the chemicals then remain in the animal’s body. PCBs can often lead to reproductive disorders or death of organisms (Derraik, 2002). Not only this, but the ingestion of the plastics also mean that chemicals are then part of the food chain, and can often bio-magnify, meaning that organisms near the top of the food chain typically have high levels of chemical pollutants found within them.
Entanglement and ingestion
Over 600 species are said to be impacted by entanglement, and an even greater amount are impacted by ingestion of plastics and other marine debris (Laist, 1997). Discarded fishing gear and plastic waste poses a huge threat to a variety of marine life, from turtles and dolphins to sea birds and fish. Organisms, such as turtles, may mistake plastic debris for food and ingest them, often causing blockages in their stomachs as well as internal lacerations, therefore meaning they can no longer feed (Independent, 2011). This is also a common occurrence in many differing sea birds.
Entanglement is also a prominent issue, as many organisms find it hard to escape once caught, meaning they become debilitated, leading to drowning, starvation, injury and in some cases death (Gregory, 2009). The IUCN highlighted that 17% of the species impacted by these issues were either threatened or near threatened (Gall and Thompson,2015), meaning that this phenomenon may have a disastrous impact on the populations.
Pathway for invasive species
Invasive species are known to be damaging to ecosystems, often outcompeting native species to become widely spread and ‘drift plastics’ are said to be a pathway from getting species from one place to another where they were not typically found (Derraik, 2002). An example of this is the bryozoan Membranipora tuberculate which is said to have crossed the Tasman Sea, from Australia to New Zealand, by encrusting on plastic pellets (Gregory, 1978). Numerous organisms such as bacteria, barnacles, diatoms and algae are believed to be moved in this way. An introduction of alien species into an ecosystem can cause disastrous impacts on diversity levels (Convention on Biological Diversity, 2016).
Greenhouse gases released by fossil fuels for energy have a large environmental impact, as they contribute to the enhanced greenhouse effect, which in turn is causing global warming to be exacerbated. Studies have shown that the use of plastics in transport, building and packaging can greatly reduce the amount of fossil fuel energy needed (Andrady and Neal, 2009). A study undertaken in 2005 concluded that using PET for packaging beverages reduces energy consumption by 52% when compared with glass and metal (Andrady and Neal, 2009). However, as plastics are usually made using fossil fuels, this energy saving may be outweighed by the negative impacts created during its synthesis.
Consumer health and safety
While plastics have a number of negative environmental impacts, one positive is that it may improve consumer health and safety. They not only provide a safe and clean mechanism for collecting and storing water, but also provide food with efficient packaging that can store food and keep it fresh for prolonged periods of time (Andrady and Neal, 2009).
Despite this, the same issues arise with chemical leaching when they are used for packaging, meaning that humans are often consuming BPA and other harmful substances. Detectable levels of BPA from plastics have been found in urine of 95% of adults in the United States, meaning that health issues not only arise in marine animals due to plastic pollution but also in humans due to their initial use (North et al, 2013).
Negative impacts on lifestyle
Subsistence fishermen in Indonesia and throughout the world are being impacted by marine plastic pollution. The way that people fish, as well as the areas they fish in are being changed by the ever increasing amount of plastic found in the oceans. Damage to gill nets and hook and line gear, as well as propeller damage and fouling have all been reported, and for people with little income, investing in replacing or repairing this gear is not feasible which often causes them to fish in differing areas or use different fishing techniques (Nash, 1992). This change in behaviour may cause a lower yield, therefore impacting families and communities in areas where subsistence fishing is relied upon (Nash, 1992). This high level of pollution is thought to be due to the lack of adequate disposal units throughout vast parts of Asia (UNEP, 2014).
Not only this, but the increase in marine pollution is likely to impact the quality of the ecosystem for future generations which may have further environmental, social and economic consequences (Vegter et al, 2014).
It is not only less economically developed nations that this impacts as 92% of Shetland have recurring problems with accumulated debris in nets, while 69% have had had their catch contaminated by debris and 92% have damaged their nets on debris on the seabed (Mouat et al, 2010).
The cost to our oceans
It is estimated that fishing boats could lose between £6,000 and £30,000 per year due to the effects and presence of marine debris, including plastic, therefore causing profit to be lost. Even in small places like Shetland, if 50% of the fishing fleet was to be affected in the same way, the cost to the industry could be £492,000–2,460,000 per year, meaning that on a global scale, the loss could be detrimental (Mouat et al, 2010).
According to the United Nations Environmental Programme (UNEP) publication of Valuing plastics in 2014, the total cost to marine ecosystems created by plastics was $13 billion. This figure incorporates the cost to fishing industry and tourism, as well as the time spent cleaning up beaches (Raynaud et al, n.d.). $1.26 billion of this cost is created in the Asia-Pacific ring alone, where many of the nations are developing, meaning that this money could be used in a far more beneficial way if plastic pollution is reduced (McIlgorm et al, 2011). A reduction in this cost is possible however, as the amount saved by consumer good companies when good management of plastic, such as recycling is implemented, is around $4 billion (Raynaud et al, n.d.).
Provision of jobs and boosting the economy
The plastic industry however, is an important part of the economy, as plastic is a highly demanded commodity. This means that it creates numerous jobs, as well as contributing to the economy due to taxes. According to Plastics Europe (2015) ‘The plastics industry is a key enabler of innovation of many products and technologies in other sectors of the economy like healthcare, energy generation, aerospace, automotive, maritime, construction, electronics, packaging or textile’, therefore showing the wide impact that plastic production has on other sectors of the economy.
However, most plastic packaging is used only once therefore meaning that 95% of the value of plastic packaging material, worth $80-120 billion annually, is lost to the economy, (Raynaud et al, n.d.). This suggests that a change in the way plastic is used needs to occur, so that the economy can benefit to a greater extent and so that the pressure on the marine ecosystem can be relieved.
What legislation is in place to prevent plastic pollution?
The Marine Strategy Framework Directive (MSFD), offers EU Member States the opportunity to take coordinated and effective action to reduce marine litter by 2020 (Surfers Against Sewage, 2014) in order to reach good environmental status in all of its waters. Measures and actions which were agreed upon in 2015 must be implemented from 2016. Following this, there will be a review in 2018 to update and review the strategies.
European Parliament and Council Directive 94/62/EC was changed in 2015 in order to meet this demand (Eur-lex.europa.eu, 2016). The directive’s mission before was to ‘limiting the production of packaging waste and promoting recycling, re-use and other forms of waste recovery ‘ but it now also ‘sets out ways and targets to reduce the consumption of lightweight plastic carrier bags, including imposing charges or setting national maximum consumption targets’ (Eur-lex.europa.eu, 2016). Since this legislation was introduced, many shops have reported a reduction in plastic bag usage, with consumption in Tesco being down by 80% since the 5p charge began (BBC News, 2015).
However, despite this change, in the European Commission Technical Assessment (Article 12) of the MSFD Obligation the UK is criticised as there has been a poor level of implementation and coordination of the directives aims. They are also said to adopt weak and un-measurable targets, which may make it hard to tell if the nation is making progress in regard to marine litter.
The UK is also subject to many other legislative protocols from United Nations Convention on the Law of the Sea (which has duties to prevent and control land based pollution making its way into the ocean); The MARPOL Convention (which prohibits the disposal of plastic at sea); The London Convention & London Protocol (plastics are on their ‘black list’ for disposal at sea) and The OSPAR Convention (which is a tool used for co-operation between nations aiming to reduce marine litter (Surfers Against Sewage, 2014).
In conclusion, it is clear that plastic pollution poses a huge threat to the environment in a number of differing ways, harming both organisms and their habitats. Not only this, but the marine litter also has social and economic impacts that are a hindrance to humans. Despite this, the industry is important globally, as without plastics, we would not have been able to develop as rapidly meaning demand is still rising (Andrady and Neal, 2009). While legislation is in place to try and mitigate the ever growing issue, I think it is most important for people to change their attitudes towards plastic consumption. Plastic is an essential part of everyday life, yet by reducing the amount of single-use plastics that are consumed, marine litter could potentially decrease. In addition to this, in the future it is essential that a greater amount of effort is put into waste management, using the Waste Framework Directive (Directive 2008/98/EC), so that a greater amount of resources can be recycled, reducing the reliance on landfill and ultimately reducing the amount of waste getting into the oceans.
By Katie Keddie