Sources, transport, measurement and impact of nano and microplastics in urban watersheds

Abstract

The growing and pervasive presence of plastic pollution has attracted considerable interest in recent years, especially small (< 5 mm and > 100 nm) plastic particles known as 'microplastics' (MPs). These particles are thought to pose greater risks than larger plastic debris as they are more likely to be ingested by many species. Their widespread presence may pose a threat to marine organisms globally. Contamination of freshwater and terrestrial systems also has been reported, and more recent studies indicate the presence of even smaller (≤ 100 nm) plastic particles, termed 'nanoplastics' (NPls), that may have unique risks due to their nanoscale. Most of the nano and microplastic (N&MP) pollution in marine environments is assumed to originate from land-based sources, but their sources, transport routes, and transformations are uncertain. Information on freshwater and terrestrial systems is lacking, and data on NPl pollution is particularly sparse. The shortage of systematic studies of freshwater and terrestrial systems is a critical research gap because estimates of plastic release into these systems are much higher than those for oceans. As most plastic pollution originates in urban environments, studies of urban watersheds, particularly those with high population densities and industrial activities, are especially relevant with respect to source apportionment. Released plastic debris is transported in water, soil, and air. It can be exchanged between environmental compartments, adsorb toxic chemicals, and ultimately be carried long distances, with potential to cause both physical and chemical harm to a multitude of species. Unfortunately, these processes are not well understood. Measurement challenges and a lack of standardized methods has slowed progress in determining the environmental prevalence and impacts of N&MPs.An overall aim of this project is to report the sources and abundances of N&MPs in urban watersheds. Their fate, transport, transformations, and potential impacts are discussed.Monitoring methods and their limitations also are reviewed, knowing that identifying N&MPs Pinto, Madhav Machavaram, and Raghuraman Venkatapathy, for their input and support.Finally, I wish to thank my family, especially my mother, Dr. M. Eileen Birch, to whom I am eternally grateful for her tremendous input and motivation throughout this project. The love and support they provided me cannot be overstated.

Presence and fate of microplastics in the water sources: focus on the role of wastewater and drinking water treatment plants

“…Among the latest reviews of peculiar interest is the one compiled by Schell et al [27] on freshwater and terrestrial ecosystems: here a specific section on WWTPs was also included, presenting one of the most up to date gathering of information on this topic. Another complete summary of the data is found in the article by Birch et al [77].…”

Editorial Overview: Emissions of Microplastics and Their Control in the Environment

“…Based on the microplastic contents in PCPs and their consumption levels, the global emission of PCP-derived MPs could reach 1.2 × 10 4 t=year (Sun et al 2020). Generally, most PCP-derived MPs enter municipal sewage networks, along with runoff and other kinds of wastewater from domestic and industrial activities, all of which contain many kinds of MPs (Birch et al 2020b). At present, conventional WWTPs are unable to completely remove MPs (Sun et al 2019).…”

“…Several reviews began to analyze the current status of knowledge on atmospheric MPs, and highlight future research needs in identifying their potential impacts on human health (Chen et al 2020a, b;Huang et al 2020;Mbachu et al 2020;Zhang et al 2020b). While still limited, research has been expanded to include specific environments, such as urban watershed, drinking water, and WWTP (Sun et al 2019;Birch et al 2020b;Danopoulos et al 2020).…”

“…Environmental controls of microplastic uptake and biomagnification in freshwater food webs MPs control in freshwater Krause et al (2020) A review: Research progress on microplastic pollutants in aquatic environments MPs in aquatic environments Tang et al (2020) Microplastics in aquatic environment: Characterization, ecotoxicological effect, implications for ecosystems and developments in South Africa MPs ecological effects in South Africa Pereao et al (2020) Source, migration and toxicology of microplastics in soil MPs ecological effects in soil Guo et al (2020) Release kinetics as a key linkage between the occurrence of flame retardants in microplastics and their risk to the environment and ecosystem: A critical review MPs ecological effects Cheng et al (2020) Bioavailability and toxicity of microplastics to fish species: A review MPs ecological effects on fish Wang et al (2020) Toward an improved understanding of the ingestion and trophic transfer of microplastic particles: Critical review and implications for future research MPs ecological effects Gouin (2020) Microplastics pollution in wastewater: Characteristics, occurrence and removal technologies MPs control in wastewater Bui et al (2020) Removal of microplastics from the environment. A review MPs control Padervand et al (2020) Microplastics and their potential effects on the aquaculture systems: A critical review MPs occurrence in aquaculture system Zhou et al (2021)Sources, transport, measurement and impact of nano and microplastics in urban watersheds MPs occurrence in urban watershedsBirch et al (2020b)…”

A Geomorphic Framework for the Analysis of Microplastics in Riverine Sediments

“…Birch et al [25] argued that because of the diversity in the size, shape and density of MPs and the range of natural environmental conditions that exist, it is not possible to make generalized statements about their transport behavior in aquatic systems. Nonetheless, the low densities some plastics (e.g., PE, PP, PS) should allow for their widespread distribution in aqueous environments as they will float near the water surface until the particles are beached along the edge of the channel, are entrapped by vegetation, or are transported onto the floodplain during overbank events.…”