Microplastics are tiny plastics that have been categorized to be less than five millimeters in length (Frias, Sobral, & Ferreira., 2010). They are toxic contaminants that have been found in marine environments, such as oceans, rivers, and lakes. The main factors that make them dangerous for the ecosystem are their long residence times, abundance in marine systems, and the high probability for marine animals to ingest it (Anderson, Park, & Palace, 2016). As a result of their presence in water systems, aquatic animals who consume them are at risk for physical and chemical harm (Ziajahromi, Neale, Rintoul, & Leusch, 2017). As of now, scientists have not yet determined the effects and long-lasting impacts of microplastics in aquatic systems, but evidence of marine animals’ deaths caused by these tiny plastics poses major concerns (Anderson et al., 2016).
The presence of microplastics can be credited towards the rise in plastic production over the last fifty years, with global production reaching over three hundred million tonnes in 2014 (Anderson et al., 2016). Microplastics fall under two categories: ‘primary microplastics’, which mainly includes microbeads found in personal care products like shampoo, and “secondary microplastics”, which are large plastics that have been degraded into microplastics (Anderson et al., 2016). Over time, they find their way into aquatic systems through ocean dumping and runoff (Andrady, 2011).
Microplastics have the potential to cause physical and chemical harm to marine animals when swallowed. Such harmful effects include their mobility being hindered, inflammation, stress on the liver, and decreased growth (Auta, Emenike, & Fauziah, 2017). Death could also occur when an accumulation of microplastics builds up in the digestive and respiratory systems, causing the airway to be blocked and toxins to be absorbed (Ziajahromi et al., 2017). Additionally, microplastics can be transferred to higher trophic levels when predators consume prey that have ingested microplastics, therefore passing the toxic effects onto the predator (Anderson et al., 2016).
The presence of microplastics in the ocean also have an effect on humans, since humans eat fish and other marine animals (Ziajahromi et al., 2017). While the immediate and concrete risks of humans ingesting microplastics is not known, it is possible that it poses numerous health risks. Ingesting high amounts of microplastics may affect the immune system, reproductive system, nervous system, and endocrine system. Low birth weight, eye secretion, facial edema, and calcifications in the skull are also some of the effects which may occur (Frias et al., 2010). There is also the possibility of microplastics entering the bloodstream (Carrington, 2018).
Raising awareness of the issue at hand will help prevent the increase of microplastic pollution in marine systems. The United Nations Panel of the United Nations Environmental Programme (UNEP) called for immediate action to reduce microplastics in the ocean by engaging forty million people in one hundred and twenty countries to promote and educate others to decrease plastic use, encourage recycling, and evaluate disposal facilities. Non-Governmental Organizations (NGOs) are also contributing by raising awareness and evaluating the scope of the effects of microplastic pollution at the national, regional, and international scale. The use of microbes to degrade microplastics is another approach to reducing microplastics in marine systems. Several bacteria species have been reported to be able to degrade plastics as a source of carbon and energy (Auta et al., 2017).
References
- Anderson, J. C., Park, B. J., & Palace, V. P. (2016). Microplastics in aquatic environments: Implications for Canadian ecosystems. Environmental Pollution, 218, 269-280. doi:10.1016/j.envpol.2016.06.074
- Andrady, A. L. (2011). Microplastics in the marine environment. Marine Pollution Bulletin, 62(8), 1596-1605. doi:10.1016/j.marpolbul.2011.05.030
- Auta, H. S., Emenike, C. U., & Fauziah, S. H. (2017). Distribution and importance of microplastics in the marine environment: A review of the sources, fate, effects, and potential solutions. Environment International, 102(Complete), 165-176. doi:10.1016/j.envint.2017.02.013
- Carrington, D. (2018, March 12). Microplastic pollution in oceans is far worse than feared, say scientists. Retrieved from https://www.theguardian.com/environment/2018/mar/12/microplastic-pollution-in-oceans-is-far-greater-than-thought-say-scientists
- Frias, J. P. G. L., Sobral, P., & Ferreira, A. M. (2010). Organic pollutants in microplastics from two beaches of the Portuguese coast. Marine Pollution Bulletin, 60(11), 1988-1992.
- Ziajahromi, S., Neale, P. A., Rintoul, L., & Leusch, F. D. L. (2017). Wastewater treatment plants as a pathway for microplastics: Development of a new approach to sample wastewater-based microplastics. Water Research, 112(Complete), 93-99. doi:10.1016/j.watres.2017.01.042