Plastic and Microplastic in the Environment. Группа авторов
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Universidad Autónoma Metropolitana Mexico City Mexico
Dhanesh Tiwary Department of Chemistry IIT Banaras Hindu University Varanasi India
Hasan Uslu Food Engineering Department Engineering Faculty Niğde Ömer Halisdemir University Niğde Turkey
Alethia Vázquez‐Morillas Universidad Autónoma Metropolitana Mexico City Mexico
Kailas L. Wasewar Advance Separation and Analytical Laboratory (ASAL) Department of Chemical Engineering Visvesvaraya National Institute of Technology (VNIT) Nagpur, Maharashtra India
Preface
Humans have modified the environment to better answer their needs, and in the process, they have changed the homeostatic mechanisms of the earth's system. The ecological fabric of the planet has undergone drastic changes due to human‐induced modifications. These changes have resulted in certain thresholds of ecological systems being broken. One such human activity is the production of waste, mainly plastic waste. Plastics are a versatile material that provides an inexpensive alternative to many industries. Plastics are a group of synthetic polymers which are now considered as an indicator of the Anthropocene. Of the 300 million tons of plastic produced each year on average, 50% of waste is designed for waste applications, i.e., it is destined to be thrown away. The European Union alone accounts for about 650 thousand tons of flexible plastic wastes. Due to its applicability, potential technology for recycling and degradation of plastic debris has become an essential issue of the 21st century. Renewable raw materials in innovative polymer products with comparable production costs and efficient technology are being explored. Global production of plastic resin has increased from about 1.5 million tons in 1950 to 322 million tons in 2015. Overall, plastic consumption has given rise to the massive load of plastic waste which has disturbed the entire ecosystem. The disposal of plastic waste is a crucial issue regardless of the present awareness and technological capacity. Plastic has been identified to be a global pollutant that now contaminates our aquatic and soil systems. Its durability and use in various industries and as disposables have resulted in a large amount of plastic in landfills and open dumps. Waste disposal is a serious concern, especially in developing countries, due to the non‐implementation of rules and lack of public mobilization. Collection, segregation, and treatment or recycling are lacking, and about 90% of the waste is still disposed of through landfills. Because the presence of plastic waste is an unrelenting concern, mainly due to its non‐biodegradability and adverse environmental impacts, there is an urgent need to tackle the plastic waste issue. A combination of various techniques is currently used to increase the energy value or reduce the waste volume of plastic wastes. Recycling of plastic waste consists of converting it into fuel or feedstock, which would reduce the volume and the net cost of disposal. Recycling converts plastics into liquids or gases with chemical, thermal, or thermo‐chemical procedures. Chemical recycling, including de‐polymerization, pyrolysis, and catalytic cracking, are the usual procedures employed by industries for plastic recycling.The omnipresence of microplastics with a size range of <5 mm is increasing worldwide concerns about their implications for human health. Its presence in water, soil, and air poses serious health risks to humans and other organisms via the food chain. However, whether these contaminants pose a substantial risk to human health is far from understood. This book emphasizes the occurrence of plastic and microplastic in the environment, challenges faced, and various management strategies and policies for their management at the global level. It also includes health risk issues related to plastic and microplastic in different componentsof the environment.
This book displays several chapters on microplastic contamination in freshwater, marine water, soil, and air. It also includes a chapter focused on microplastic in various aquatic food chains and its impact on human health. It includes and highlights several techniques related to microplastic detection in different environmental media. Chapters on the distribution of plastic at the global level and challenges related to its recycling, degradation of plastic, and biodegradable plastic are also included. It also includes a chapter on the role of education and society to deal with plastic problems. This book will be helpful for graduate students, researchers, engineers, technologists, NGOs, and government agencies working in plastic and microplastic related issues.
This book is a humble effort to address the plastic and microplastic issues across the globe. We hope that it is an important addition to the available literature. The contributors of the book are from diversebackgrounds that provided holistic information on the topic. We convey our heartfelt gratitude to all the contributors and publishers who helped to produce an incredible and meaningful edited volume on a very relevant theme.
1 Sources, Occurrence, and Analysis of Microplastics in Freshwater Environments: A Review
Anh Tuan Ta and Sandhya Babel
School of Biochemical Engineering and Technology, Sirindhorn International Institute of Technology, Thammasat University, Pathum Thani, Thailand
1.1 Introduction
Plastic products have benefited human life for one hundred years. Plastics are used in almost every sector including construction, packaging textiles, consumer products, transportation, electronics, industry, and medical applications. These products make our life more comfortable, convenient, and safe. The world plastics production in 2018 was about 360 million tonnes (PlasticsEurope 2018). However, due to poor management, about 10% of plastic wastes are discharged into aquatic environments (Cole et al. 2011). Recently, considerable attention is placed on the distribution of micro‐sized plastic particles, so‐called microplastics (MPs). The ubiquity of MPs has been widely documented in the marine environment, and their possible impact was investigated (Dris et al. 2018). MPs are frequently ingested by organisms, either from ingestion of other organisms containing MPs, or because they cannot distinguish MPs from prey (de Sá et al. 2015). This may cause physical harm for organisms including a disruption of the hormone balance or digestive system, reduced feeding, and impacting reproduction (Carr et al. 2012; Lusher et al. 2013). Another ecological risk relates to the interaction between MPs and toxic chemicals. The small plastic debris has a high surface area to volume ratio that can enhance the interaction of toxic chemicals onto their surface (de Sá et al. 2018). These chemicals may be carried by MPs over long distances and accumulate in organisms after being ingested (Bakir et al. 2016; Lee et al. 2014). Another potential risk is that MPs can be vectors of microorganisms that attach to their surfaces (Viršek et al. 2017). Human pathogens have been found to colonize on MP particles in marine environments (Foulon et al. 2016; Kirstein et al. 2016). However, the existence of MPs in aquatic environments is complex as they have different polymer types, morphologies, sizes, states of degradation, and contain different additives. Therefore, the evaluation of MPs toxicity is still hampered. Until now, most studies on MPs have been conducted on marine environments; while in contrast, the distribution of MPs in freshwater environments has been investigated less. To highlight this, a study by Blettler et al. (2018) found that 87% of MP studies were related to marine environments, while only 13% of the studies were on freshwater environments. A few studies reported that rivers can transport a huge amount of plastic and MPs into oceans; according to Schmidt et al. (2017), rivers contribute 88–95% of plastic wastes placed into the oceans. Methods for the identification of MPs have been developed by many researchers; however, these methods are not homogeneous and standardized, and this hampers the comparison between different studies (Li et al. 2018; Van Cauwenberghe et al. 2015).
This chapter reviews the current state of MPs in freshwater systems, and different techniques for sample collection, preparation, and analysis of MPs are summarized. Moreover, the potential sources, pathways, and occurrences of MPs into freshwater systems are discussed in the chapter.
1.2 Sources of Microplastic
MPs originate from various sources, but they are mainly