Plastic waste imposes a tremendous global challenge that threatens the well-being of animals, marine and terrestrial biotas. Plastic waste is escalating at an alarming rate of 4.8-12.7 million tons of mismanaged plastic entering oceanic spaces and 32% of all plastic finding its first receptacle in soils or continental aquatic ecosystems. While nature suffices at fragmenting plastic when entering oceans, processes such as biodegradation may take centuries to be completed, which hints at the possibility of oceanic spaces being filled entirely with mismanaged plastic and waste if left untreated. Despite the longevity of the biodegradation process, physical degradation is very instantaneous in comparison: leading to microplastic divergence across different compartments such as major open oceans, deep oceans, fresh lakes, and water spaces, even as far as the arctic sea ice and atmospheric fallout.
The scope of mainstream scientific research has been recently readjusted to involve research on microplastic threat on our planet. As a matter of fact, the term microplastic was first used in 1990 by Ryan Thompson and Moloneys in their research on plastic in South African beaches. Nevertheless, the term was only endorsed by the scientific community/codified into the prevailing narrative among international institutions in 2004 after Thompson’s paper examined Microplastics in Plymouth beaches, UK. Thus, with its recent debut into the scientific research community, Microplastics research was predominantly overlooked, and the areas explored were almost always tied to the plastic—of normal sizes—in essence.
The term microplastic refers to plastics that exist in sizes less than 5mm, these forms of plastic are very persistent in the environment. Hence, the long-term impact they induce upon the ecosystem in which they exist. Due to the increased market and value and dependency on its products, plastic production has been escalating at an exponential rate that in 2015 it reached a peak of 381 million tons. Hence, prompted initiatives and policies that ban plastic products, such as The United States Microbead-free waters Act in 2015. This act aims to prevent the use of plastic products of <5mm sizes, which predominantly exist in rinse-off personal care products, abrasive scrubbers (i.e, facewash, body wash, and toothpaste).
Nevertheless, the act was disputed for two critical observations being: The act was very specific to a type of microplastic (Microbeads), which does not amount to the affluence of other sources that generate microplastic. Moreover, it utterly disregards the second source of plastic which fragments into microplastic and is considered a major source of plastic pollution. Secondly, all plastic materials were equally treated irrespective of the implications, which generalized products with little or no impacts, such as bioplastic. However, the act assisted in the progression of policy-making and the standardization of a policy that can factually prevent the escalation of plastic waste.
Microplastics are driven from two main sources: Primary plastic and Secondary plastic.
Primary is referring to plastics that were produced in micro sizes. Examples of these sources can be found in pellets, personal care products, and fibers utilized in the textile industry.
Secondary sources which are predominantly dominant are exemplified in plastic of a wide range of sizes that biodegrade into micro sizes. This process evidently takes longer to generate MPs (microplastics) in the ecosystem. However, it is still considered superbly harmful to the marine and terrestrial biota. Secondary sources are mostly thermoplastics which include: PE, PS, PP, and PVC, these are mostly implemented in the production of plastic bottles, plastic bags, fishing nets, and food containers.
Over eight million tons of plastic have been reported to exist in marine ecosystems, and with the presence of degradation factors, these plastics are rapidly turned into microplastic particles. These Microplastic particles can impose a fatal threat on their surroundings. For instance, these particles induce blockage of digestive tracts—eventually, leading to loss of energy intake for the biota, which can threaten the balance of the trophic chain. Moreover, it can alter the enzyme secretions, which factually affects the consumer of said affected organism. Finally, it can induce alternation in heartbeats, which predominantly corresponds to heart attacks, and sometimes cancer.
A recent study presented that MPs of types PA, PE, PS, PP, and PVC can cause intestinal damage in that it devours the villi and tears apart the enterocyte. Similarly, it was discovered that digestion of MPs engenders reproductive dysfunctions, reduction in calcium levels in the intestine, and exponential expression of oxidative stress genes.
For humans, it was found that the annual consumption of MPs was 41106 ± 7124, 51814 ± 8172, 38722 ± 6977, 46013 ± 7755 for Male children, Male adults, Female children, and Female adults, respectively. Similarly, the annual inhalation of MPs was 40225 ± 44730, 61928 ± 68865, 35338 ± 39296, 35338 ± 39296 for Male children, Male adults, Female children, and Female adults, respectively. Microplastic pollution can be linked to numerous varying factors. For instance, extreme weather effects such as hurricanes, storms, or any unstable weather manifestation can rapidly transport plastic particles from one system into another. Similarly, human intervention such as urbanization, littering, improper waste management, plastic mulching, and sewage sludge applications can all induce the same effect on plastic transportation, which originated the notion that a phenomenon such as the “plastic cycle” does exist wherein plastic can move across large compartments and from a system into another. Which, quintessentially differs from the initial model that viewed MPs can move between minuscule compartments: tissues.
Amid degradation, plastic ruptures into its own composing materials, which include Phthalates and Polybrominated diphenyl, Bisphenol that are used to maximize the plasticity, fire resistance, and anti-microbial qualities.
Microplastics' presence is an explicit outcome of human’s centuries-long effect on the environment; simultaneously humans are capable of ceasing the rapid proliferation of this material. That can be demonstrated through initiatives to recycle or to examine and study the MPs and assess its source with preventive measurements. Factually, the items that overwhelmingly make up our plastic use—plastic packaging and bottles—approximately 80% of them are recycled. However, recycling at times can be superbly inaccessible to certain groups of the population, which renders retention of plastic materials in landfill to face its fate in marine and freshwater ecosystems eventually. Thus, there should be an intervention on the policy level. Political leaders, and nonprofit organizations should promote cut-on plastic use—especially the ones that are frequently used: plastic bottles, bags, packaging, etc. The policy should be devised with intrinsic (Lasting and/or of perpetual impact) long-term effects to ensure that the effects led by it are lasting and impactful for future generations.
When policies are concerned with individuals’ behavior--especially when it comes to plastic use or misuse thereof-- policymakers must include elements to help uplift the implementation of said policies. Said elements should involve: educating the masses about microplastics and their origins, pursue legislative action to omit the application of any form of micro-sized plastic production, devise public campaigns that can appraise citizens on the importance of cutting on plastic use, especially the secondary sources.
Works Cited
Pahl, S., Wyles, K. J., & Thompson, R. C. (2017). Channelling passion for the ocean towards plastic pollution. Nature Human Behaviour, 1(10), 697–699. https://doi.org/10.1038/s41562-017-0204-4
O.S. Alimi, O.O. Fadare and E.D. Okoffo, Microplastics in African Ecosystems: Current knowledge, abundance, associated contaminants, techniques, and research needs, Science of the Total Environment (2020), https://doi.org/10.1016/.scitotenv.2020.142422
Cox, K. D., Covernton, G. A., Davies, H. L., Dower, J. F., Juanes, F., & Dudas, S. E. (2019). Human Consumption of Microplastics. Environmental Science & Technology, 53(12), 7068–7074. https://doi.org/10.1021/acs.est.9b01517
McDevitt, J. P., Criddle, C. S., Morse, M., Hale, R. C., Bott, C. B., & Rochman, C. M. (2017). Addressing the Issue of Microplastics in the Wake of the Microbead-Free Waters Act—A New Standard Can Facilitate Improved Policy. Environmental Science & Technology, 51(12), 6611–6617. https://doi.org/10.1021/acs.est.6b05812
Sharma, S., & Chatterjee, S. (2017). Microplastic pollution, a threat to marine ecosystem and human health: a short review. Environmental Science and Pollution Research, 24(27), 21530–21547.https://doi.org/10.1007/s11356-017-9910-8