A Global Perspective on Microplastics

Abstract

Society has become increasingly reliant on plastics since commercial production began in about 1950. Their versatility, stability, light weight, and low production costs have fueled global demand. Most plastics are initially used and discarded on land. Nonetheless, the amount of microplastics in some oceanic compartments is predicted to double by 2030. To solve this global problem, we must understand plastic composition, physical forms, uses, transport, and fragmentation into microplastics (and nanoplastics). Plastic debris/microplastics arise from land disposal, wastewater treatment, tire wear, paint failure, textile washing, and at-sea losses. Riverine and atmospheric transport, storm water, and disasters facilitate releases. In surface waters plastics/microplastics weather, biofoul, aggregate, and sink, are ingested by organisms and redistributed by currents. Ocean sediments are likely the ultimate destination. Plastics release additives, concentrate environmental contaminants, and serve as substrates for biofilms, including exotic and pathogenic species. Microplastic abundance increases as fragment size decreases, as does the proportion of organisms capable of ingesting them. Particles <20 μm may penetrate cell membranes, exacerbating risks. Exposure can compromise feeding, metabolic processes, reproduction, and behavior. But more investigation is required to draw definitive conclusions. Human ingestion of contaminated seafood and water is a concern. Microplastics indoors present yet uncharacterized risks, magnified by the time we spend inside (>90%) and the abundance of polymeric products therein. Scientific challenges include improving microplastic sampling and characterization approaches, understanding long-term behavior, additive bioavailability, and organismal and ecosystem health risks. Solutions include improving globally based pollution prevention, developing degradable polymers and additives, and reducing consumption/expanding plastic reuse.

The physical oceanography of the transport of floating marine debris

“…With the growing attention on marine plastic debris by scientists and the public alike, there has been a plethora of scientific reviews in the last few years (e.g. Andrady 2011, Law 2017, Zhang 2017, Hardesty et al 2017a, Kane and Clare 2019, Maximenko et al 2019, Amaral-Zettler et al 2020, Hale et al 2020. However, none of these reviews focus exclusively on the physical processes that control the transport and the resulting distribution of plastic debris on all spatial scales, ranging from the ocean gyres to beaches.…”

Microplastics provide new microbial niches in aquatic environments

“…They are accumulating at increasing speed in aquatic environments, such as lakes and rivers, which act as “plastics collectors” from their terrestrial surroundings/watershed (Koelmans et al 2019 ; Zhang et al 2018 ). This could pose a potential threat to humans via ingestion of contaminated fish and seafood (Hale et al 2020 ; Skåre et al 2019 ). The behaviour and fate of microplastics in freshwater, estuarine, marine and terrestrial environments are therefore receiving extensive study (Akdogan and Guven 2019 ; Amaral-Zettler et al 2015 ; Andrady 2011 ; Burns and Boxall 2018 ; Galloway et al 2017 ; Horton et al 2017 ; Koelmans et al 2019 ; Oberbeckmann et al 2015 ; Sharma and Chatterjee 2017 ; Zhang et al 2018 ).…”

Multispecies Sustainability

“…Even those in extreme environments such as deep sea vents are still part of tremendously complex food webs and trophic cascades (Govenar, 2012). Human-induced global changes to the Earth system, such as climate change, ocean acidification and microplastic pollution, further make unlikely the existence of species being wholly independent and unaffected (Capra & Luisi, 2016;Doney et al, 2009;Hale et al, 2020;Pecl et al, 2017;Steffen, Broadgate, et al, 2015). The ecosystemically-related zoonotic origin of the recent Covid-19 pandemic represents another hint in this direction (Bonilla-Aldana et al, 2020).…”