Microplastic Pollution

Plastic particles <5 mm come under the category of microplastics (MPs) that can be primary or secondary in nature. Microplastic pollution is a major concern because the world’s shores served as a major sink. Previously, the researchers focused on marine ecosystem, whereas the data on beach sediments and water are limited, especially in South Asia. Several research articles have been published in South Asia, including India, Pakistan, Sri Lanka, Maldives, and Bangladesh. Furthermore, Nepal, Afghanistan, and Bhutan lack information regarding MPs on beach sediments and surface water. Therefore, the review in South Asia will help mitigate and raise awareness on the severity of MPs within the research community and local public. Here, we review the abundance, fate, spatial distribution, research need, and gaps regarding MPs. In Pakistan, only two research articles are published despite the higher concentration of MPs there compared with the other South Asian countries. High concentrations of MPs on sediments (3726 particles/m²) and fresh water (2074 particles/m³) were observed in Ravi River, Lahore, whereas low MP concentrations on sediments (22.8 particles/m²) and fresh water (0.32/m³) were observed in Faafu Atoll, Maldives. In terms of shape, fragments were dominant with the polyethylene polymer type. MP pollution mainly depends on population density, where land-based sources, i.e., industrial, municipal, fishing, tourism, and recreational activities, are the major contributors. Consumption of MPs is life-threatening. The chronic biological effects in aquatic organisms are due to the accumulation of MPs in their cells and tissues. Understanding of these areas is essential to raise awareness and establish management policies for decision-making in this perspective.

Plastic products in different sizes and with different features are in widespread use to make day-to-day life easier. Until now, these materials have not been considered as a threat to terrestrial and aquatic environments; however, the accumulation of these products in these environments is now considered to cause plastic pollution. Consequently, plastic wastes and their degradation byproducts have become a more serious problem to overcome. The level of anthropogenic pollution defines as the level of plastic pollution. Efforts encompassing all known methods for plastic pollution mitigation have been attempted, but as yet, an effective solution has not been found. In the last 40 years, MPs have gained a significant attention as one of the emerging pollutants in the aquatic environment. The expansion of the occurrence of MPs in fresh water and seawater globally results in having a great deal of attention by scientists, policymakers, and the public. The determination and comparison of MPs abundance and characteristics are still not understood well as MPs study is in its early years. The studies on MPs’ spatial and temporal variations in aquatic systems should be increased worldwide. In this chapter of the book, principal methods in microplastic isolation such as sampling, separation, and identification have been attempted to comply with microplastic research to be performed in various matrices of freshwater and marine ecosystems. Also, new techniques and methodologies that are preferred for use in microplastic studies will be explained.

The tendency for plastic leakage into the environment is increasing, and researchers struggle to detect the increase of plastic particles in marine environments. However, this situation raises a heated debate about the fate and final destination of missing plastics. The main axis of these discussions is whether the polymer types of plastics are also the determinants of the fate of plastics. It is necessary to know the polymer types of microplastics in all marine environments to understand whether this is so. Most of the studies conducted in this context examine microplastics in sea surface water and on the seabed. Although the highest number of microplastics are found in the seabed and the sea surface water, various studies emphasize that microplastic concentration in coastal ecosystems also increases. The major factor that determines the extent of microplastics in coastal environments is their density and polymer types. Therefore, it is possible that different polymer types of microplastics can be found in different marine compartments depending on their density. This chapter evaluates the presence and diversity of some of the produced microplastics in coastal areas. It can be said that the coastal environments are the main accumulation areas of microplastics, especially for types such as polypropylene and polyethylene, which have the highest production rates. 

Since the plastic frenzy began during the last century, the contamination of air, water, soil, and biota with microplastics, the degraded metabolites of plastics, has become a subject of environmental research. Resolving the issue requires the tracking of microplastics back to their sources. Environmental forensic approaches have the potential to tackle this ubiquitous challenge, but their application faces serious hindrances. The questions concerned with the manifestation of the problem to the transport, eventual fate, and source identification are still to a large extent unanswered. These issues are faced due to the poor understanding of interconnectedness of environmental metrics and lack of standardized data. This review is conducted with the purpose of assessing potential routes of microplastics by understanding the sink-source identification techniques and to determine the effectiveness of different metrics for the study of microplastics and their application as a tool in environmental forensics and other relevant fields.

The use of plastic products is common in our day-to-day life due to its unique properties. But its mishandling and poor waste management lead to its accumulation in the environment. In the environment, it may degrade by different environmental factors such as photo-oxidation and thermal and biological degradation, resulting in particles with a size less than 5 mm called microplastics (MP). These particles are of major concern because they have been detected through different environmental compartments and pose a serious threat to the organism’s as well as to human health. MPs are highly persistent and stable in the environment and have long residence time. The environmental pollutants may also adsorb on its surface, that may leach or desorb once into the living body. Furthermore, the presence of these particles in the environment leads to bio-accumulation and bio-magnification in different trophic levels causing adverse human health impacts. The main aim of this study is to highlight the sources, occurrence, and behavior of microplastics in the terrestrial environment. Additionally, this chapter focuses on the impacts of microplastics on human health.

Microplastic (MP) pollutants are widespread and have been detected in both surface waters and sediments across the globe. At some places, MP abundance reached 90–100% of the samples sampled in surface waters. They (MP) have even reached the remote and pristine parts of the world. Plastic litters have outnumbered fish larvae and plankton at several places in the world. The increased abundance of MP was reported in surface waters close to larger cities and cities with higher population density, enclosed basins, gyres, dams/reservoirs and coastal areas. The Coastal Soya Island, South Korea (having 46,334 MP particles/m²) and the Pearl River Estuary, Hong Kong (having 5595 MP particles/m²), are the two MP pollution ‘hot spots’ in surface waters. MP pollutants are also widespread and detected in sediments of a wide range of aquatic environments including archipelagos, bays, channels, coasts, beaches, deep seas, estuaries, lagoons, rivers, shellfish farms and ship-breaking yards. At some places, MP abundance in sediments reached around 64% to 100% of the samples sampled. The Kachelotplate and Spiekeroog islands, Germany (having 38,000 MP particles/kg dw sediments) and Jakarta Bay, Indonesia (having 30,006 MP particles/kg dw sediments), are the two MP pollution ‘hot spots’ in sediments. Based on polymer shapes, the most commonly detected MPs in both surface waters and sediments are fibres, fragments, foams and films. On the other hand, based on polymer chemistry, the most commonly detected MPs in surface waters and sediments are polyethylene (PE), polypropylene (PP) and polystyrene (PS). To reduce impacts from plastic wastes and plastic pollution, a number of measures have been suggested.

Microplastic pollution is one of the most important problems of today. The prevalence of microplastics in the marine environment, as well as their consequences on marine biota, is evident. The Black Sea has been rapidly polluted in recent years and has been described as one of the most affected areas. Microplastics are quite intense from the data obtained from the studies on marine litter and microplastics in the Black Sea. It is also very important to have information about the distribution and sources of microplastics for the Black Sea Region. The purpose of this review is to provide a general assessment of the microplastic pollution of the Black Sea.

Microplastics are one of the emerging pollutants in the world. This pollutant is present in all parts of the environment, especially in water. The principal sources of microplastics in water are divided into two categories, primary and secondary. The primary microplastics are primarily produced in micrometer sizes in factories and enter the water through the wastewater treatment effluent. However, secondary microplastics originate from the decomposition of larger plastics deposited in shorelines and gradually enter the water over time. Microplastic entry into the water also occurs through transporting from the atmosphere and soil; for example, microplastics in the atmosphere can deposit on the soil surface or into the water. In addition, microplastics in the soil can be washed into freshwater through runoff and eventually enter the seas and oceans. Ultimately, the microplastics in the water either settle into the sediments or enter the body of aquatic organisms in various ways. Therefore, accumulating microplastics in the body of aquatic organisms originates health problems. Furthermore, microplastics can cause problems for humans who may consume them as seafood. Therefore, it is clear that there is an urgent need to develop removal methods for this contaminant. Wastewater treatment plants cannot entirely remove microplastics, so specific removal techniques are being developed in recent years.

Healthy freshwaters contribute to the conservation of a wide range of species and provide several ecosystem services indispensables for our society. However, freshwater contamination is an issue requiring awareness and management actions. Microplastics are one of the latest persistent pollutants in freshwaters, widespread worldwide, and to date contaminating rivers and lakes of all continents. In this chapter, we provide an overview on the occurrence of microplastics in freshwaters, mainly discussing (1) methods detecting them in rivers and lakes, (2) contamination quantification and localisation, (3) observations on impacts due to microplastics on biota and (4) plastic pollution origin.

Due to the increasing plastic production in the world, it is predicted that the amount of microplastic will increase in the future in all ecosystems in the world, especially in aquatic ecosystems. It is obvious that the negative effects of this pollution will increase in the same way. In this section, the coastal ecosystem, which is an important part of aquatic ecosystems, and the status of microplastic pollution in beaches, estuarine regions and sea meadows, which are important parts of this ecosystem, have been compiled from recent publications.

Numerical models are strong tools to understand the dynamics better and analyze the sources, transport, receptors, and consequences of microplastics in the coastal environment. Complex dynamics and interactions of biotic and abiotic components of aerial, terrestrial, aquatic, and benthic processes make the numerical modeling of microplastic transport challenging. In this chapter, we presented an overview of modeling aspects consisting of sources and sinks of microplastics, key processes affecting their transport and fate, types of coastal systems, physical properties of microplastics important for the numerical modeling studies, types of modeling approaches, data requirements, and tools for numerical simulations.

Plastic pollution has escalated during last 50 years. The estimated value of plastic content in marine environment is more than 250,000 tons. Microplastic (less than 500 mm in diameter) accumulation in seas and oceans is the new potential environmental concern because of its rapidly increasing concentration in marine water, sediments, and marine animals. These are introduced into the environment either through primary sources, which include plastic pellets, microbeads, and glitters, or secondary sources which are microplastic dust, water treatment plants, wear and tear from normal use, and large objects that produce secondary microplastic upon deterioration, etc. Particles as small as 0.01 mm to <5 mm have been found in oceans worldwide. They exist in different shapes like fiber, film fragment, granules, and spherules and consist of different polymers like polyethylene, polypropylene, polystyrene, low- and high-density polyethylene, thermoplastic polyurethane (TPR), nylon (NYL), polyvinyl chloride (PVC), ethylene propylene rubber (EPR), acrylonitrile, and styrene. Concentration of microplastic can be expressed in the number of particles per cm², m², m³, or km². Maximum concentration of microplastic in terms of particles per meter cube is 15,560 recorded in Southeastern Sea, Korea, whereas, in terms of the number of items per km², it is 360,000 items at North Atlantic Ocean (subtropical gyre). Bohai Sea and Suva Harbour of Urban Coast of Fiji appear to be least contaminated with microplastic. Marine animals like mysids, mollusks, and fishes are ingesting microplastic and dying as a result of its accumulation in their stomach. MP particles also reach higher trophic levels through the process of biomagnification. Keeping these things in view, scientists either suggest imposing ban on the production of certain plastic type or formation of rules and regulation on the production, usage, and throwing off plastic items in order to control the ever-increasing levels of microplastic pollution in marine water.

This chapter collected, collated, analysed, synthesised, interpreted and documented the last 15 years (2006–2021) of research investigations carried out on microplastic (MP) pollution impacts on seafood organisms including fish, sharks, oysters, mussels, shrimps, lobsters and seaweeds covering 36 locations or countries in the world (the Atlantic Ocean, Australia, the Baltic Sea, Bangladesh, Belgium, Brazil, Canada, Chile, China, Fiji, France, the Gulf of Mexico, India, Indonesia, Iran, Italy, Japan, Malaysia, the Mediterranean Sea, the Netherlands, North Pacific Central Gyre, North Pacific Subtropical Gyre, North Sea, Norway, Portugal, Saudi Arabia, Scotland, South Pacific Subtropical Gyre, Spain, Tanzania, Thailand, Turkey, the UK, the USA and Vanuatu). Elevated/high levels of MP ingestions (compared to other species investigated by researchers) were found in 47 seafood species (39 fish, 1 shark, 3 molluscs, 3 crustaceans and 1 seaweed). MP particles ingested by seafood organisms were highly variable and found related to feeding habits and habitats of the species. MP ingestion rate in seafood organisms varied between 3% and 100%. Higher ingestion (>30%) was reported from the Atlantic Ocean (fish), Australia (fish), Belgium (shrimp), Brazil (fish), Chile (fish), China (fish), China (seaweed), Fiji (fish), France (fish), India (fish), Italy (shark), Japan (fish), Malaysia (fish), North Pacific Central Gyre (fish), Portugal (fish), Scotland (lobster), South Pacific Subtropical Gyre (fish), Spain (fish), Thailand (fish), Turkey (fish), the UK (fish), the UK (shark), the USA (oyster) and Vanuatu (fish). Fibres were the major polymer (by shapes) ingested by seafood organisms (ingestion rate ranged from 33% to 99%). Black, blue, green, orange, purple, red and white were the coloured polymer ingested by various seafood organisms. The higher MP ingestion in seafood organisms may have occurred due to a number of reasons including the following: (1) the study might have been carried out in MP pollution ‘hot spot’ areas, (2) fish and other organisms that accidentally/mistakenly ingested MPs during their normal feeding activity (confusing MPs as prey/plankton/food) or (3) MP ingestion has occurred through trophic transfer from their prey species (as fish foods such as amphipods, copepods, decapods and euphausiids larvae are known to ingest microplastics). Polymers ingested by seafood organisms can adsorb persistent organic pollutants/priority pollutants (heavy metals, PAHs, DDT, PCBs). In addition, plastic additive chemicals (phthalates, bisphenol A, heavy metals, flame retardants) can leach out to the aquatic environment or ingested biota. Therefore, both adsorbed and additive chemicals may be transferred to humans via the consumption of contaminated seafood (fresh fish, whole fish, canned fish and dry fish). The possible human health effects of consuming MP-contaminated food and water include damage of both DNA and cells and inflammation reaction.

Rapid urbanization and industrialization have introduced a variety of organic pollutants in the environmental matrices. Some of these chemicals are resistant to degradation and are termed as persistent organic pollutants (POPs). Humans and other living organisms have become highly susceptible to these environmental contaminants. For example, the semi-volatile organic compounds such as bisphenol A (BPA), phthalate esters (PAEs), and styrene monomers (SM) are extensively used in industrial production and served as intermediate complexes in different products used in daily activities. They have been classified as endocrine disruptors; therefore, exposure to these toxins creates various complications in humans and other living organisms in various ecosystems. Consequently, a balance is disturbed in the ecosystems, disintegrating the dependence of organisms on abiotic and biotic factors. This article aims to provide an overview of the commonly used plasticizers and their classification and applications, fate and transport, metabolism and mechanism of action. Subsequently, pollution load in different matrices of the riverine ecosystem has been targeted with special emphasis on the shift in ecological integrity. In addition, concerns over the use of these chemicals and their exposure have been highlighted that reflect a dire need to restrict and minimize their use to retrieve the ecological equilibrium.

Anthropogenic activities, particularly urbanization, have fragmented natural habitats. Generation of waste is perhaps one biggest consequence of human activities. Production, use, and disposal of plastic-based products have led to the generation of humongous quantities of waste which has its repercussions not only for the man himself but also for the other living organisms. Because of the incessant urban sprawl, various organisms are forced to adapt themselves to the man-made urban habitats, known as urban species. Birds are one such group of highly urbanized species, which by the virtue of their ability to fly, can quickly move from one place to another in search of food and nesting sites. Indiscriminate use of plastic and resulting production of plastic waste have replaced naturally available food and nesting material. This alteration in the natural environment has led to a significant impact on the ecology, and thus foraging and nesting behavior of birds. There have been several stances whereby birds have ingested plastic pieces mistaking it for food. Gut analyses of marine and terrestrial birds have revealed the prevalence of meso- as well as microplastics from direct and indirect ingestion. Likewise, in the absence of natural vegetation-based material, and because of the abundance of anthropogenic material, birds have been found to incorporate items like polyethylene bags, plastic sheets, plastic wires, yarn, etc. in their nests as a structural, defensive, or insulation component. Ingestion of plastic in birds has been linked with stomach obstruction and perforations. Likewise, plastic incorporation in nests has been associated with entanglement and even death of the nestlings by strangulation. These consequences of plastic trash on behavior and ecology of birds clearly highlights mankind’s lacking diligence toward environment and the repercussions of his actions on the components of the ecosystem.

Microplastics are stubborn pollutants that are growing in attention in the twenty-first century. These pollutants are ubiquitous in the entire environment. The endurance of microplastics poses it is greatly resilient to decay and enables it to reach into the natural environment. Owing to its tiny nature, microplastics can be accessed readily and subsequently transported via the food web by many species from marine, freshwater, and terrestrial ecosystems. The ingestion of microplastics in the body tissue of marine and freshwater creatures, as well as terrestrial creatures and plants, causes severe biochemical consequences. Indirect intake of microplastics has also the prospects to produce genetic changes in human beings that might induce sterility, obesity, and chronic cancer. Due to the risk of microplastic pollution to the entire ecosystem and mitigating the environmental pollution risk, overuse of plastics and plastic-derived products must be controlled, and laws and strategies to restrict the origins of plastic debris must be implemented. In addition, in-depth research is required to fully quantify the adverse impact and environmental concerns of microplastics in marine, freshwater, and terrestrial ecosystems.

Spatial and temporal variations of microplastics (MPs) studies in both fresh water and seawater ecosystems have produced many results that support the adsorption of toxic pollutants to the microplastic surface. In addition, small-sized polymer fragments have increased their participation in the food web since phytoplanktonic organisms. This situation causes consequences that can severely limit the growth and/or development of many aquatic species. In this part of the book, the toxicity studies results examined in the last 10 years show that the properties of microplastics (polymer type, shape, size, colour, etc.), the exposed dose, the forms of exposure and the way in which functional disorders occur afterwards are addressed; methodically and conceptually. In the methodology studies of toxicity studies, it was determined that the most preferred microorganism was Daphnia magna. Many factors taken into account due to the ease of operation of the organism, the clarity of the test procedures, its comparability and the purpose of the studies carried out are effective in these choices. In addition, Danio rerio, Mytilus galloprovincialis, Mytilus edulis and Scrobicularia plana were found to be among the other organisms of frequent choice.

Toxicology studies focus more on the effect of exposure to a single concentration or independent chemicals. Therefore, researchers have struggled to find answers to the type of interaction. The movement and dynamic of microplastics in water, the similarity of MP colour to nutrients for the organism or pollutant absorption due to surface load affect the accumulation of pollutants in the organism. In addition, it has been observed that polymer type is an important factor in determining microplastic toxicity, while polypropylene (PP) is the most common type of microplastic in detection and analysis studies, toxicology and MP studies have shown that studies on polyethylene (PE) and polystyrene (PS) are high. The pressure of these polymers on each step in the food web, when additives used in the plastic manufacturing process are added, leading to toxicology results reach to a toxic or very toxic level.

Humans and ecosystems are constantly exposed to microplastics (MP). The magnitude of contamination, their ubiquity, and high persistence over time raise serious concerns about their effects on ecosystems, wildlife, and human health. MP represent a diverse class of contaminants occurring on a continuum of sizes and in various shapes and presenting a complex composition that includes several types of polymers and several associated pollutants. In short, MP are perhaps one of the most challenging contaminants created by humankind. The effects of exposure to these pollutants are of growing concern even though the type and level of exposure and the specific risks for humans and ecosystem health have not yet been entirely determined. In this chapter, we identify critical qualitative and quantitative aspects of MP sources and exposure routes and toxicity profiles and confront them with research on MP effects and estimations of risks to human and environmental health. Finally, we highlight that some novel sources of MP contamination pose a serious risk of exposure to humans and ecosystems, such as nanoplastics and the recycled plastics incorporated into road pavements and construction.

Microplastics are widely distributed across the different environments by means of which they affect the various living organisms. This distribution majorly arises from dumping of plastic wastes into landfills and sewage treatment systems. This chapter focuses on the occurrence of microplastics in the environment and its treatment technologies. Landfills serve as the main source of plastic pollution in the environment. It slowly disintegrates into microplastics by weathering processes. Sewage treatment plants are effective in removing up to 99.2% microplastics from the sewage. However, further investigation is needed to develop treatment technologies for the removal of microplastics from landfills and for the complete removal (100%) of microplastics from sewage.

In the current situation, to tackle global climate change and minimize plastic pollution, many countries are enacting policies and strict rules on the usage and alternatives of plastics. As a result, understanding the mechanisms of microplastic release into environmental materials is critical such as water interaction to mitigate the problem as effectively as possible. The primary goal of this study is to integrate plastic waste management and current statements of green treatment technologies for microplastic pollution to help sustain the environment and furthermore to improve sustainability by meeting our communal requirements without causing further harm or depletion of the remaining natural resources and developing alternative production methods to replace those that have been shown to harm human health and to decrease environmental plastic pollution. The sorption capability at the regolith showing a progressive bond with the concentration of microplastics as concentration increasing the sorption capacity also increases, and desorption study with water showing the microplastic particles is easily absorbed. The microplastics waste green treatment technologies such as to reduce and conserve plastic usage and its associated nonrenewable energy sources and to safeguard biodiversity, habitats, and biotas to confirm that future generations will be able to fulfill their own needs.

Microplastics (MPs) are semisynthetic plastics having diameter less than 5 mm and considered as one of the most abundant pollutant in environment. MPs become part of the environment by the breakdown of larger plastics or through the release of plastic feedstock like pellets, nurdles, and microbeads from industries into the environment. MPs have also been identified in every marine habitat (beaches, surface water, deep seafloor) around the world. There are various chemical techniques used for the degradation of MPs which include advance oxidation processes such as photocatalysis, photodegradation, chlorination, and coagulation, agglomeration, flocculation, and chemical weathering. Photocatalysis is most extensively used because undesired products are not formed. Photodegradation involves the exposure of material to lighten ambient conditions resulting in the formation of free radicals of microplastics. Degradation of microplastics depends on intensity of light as well as nature of environment in which photodegradation occurs. MPs can be degraded using chlorination. Chlorination breaks the bond and introduces the new bonds between chlorine and hydrogen. Coagulation/flocculation/agglomeration processes entail the formation of large-sized particles of MPs by using salts of Fe and Al and other coagulants. Electrocoagulation is robust, is cost-effective, is energy efficient, is environmentally friendly, produces minimum sludge, and is resilient to automation. Chemical weathering processes cause fragmentation, alter the chemical composition along with decrease in molecular weight, and destroy thermal and mechanical properties of microplastics.

Microplastic pollution has emerged as a severe transboundary threat to natural ecosystems, marine environments, and human and nonhuman health. Microplastic pollution and its consequent impacts on natural ecosystems and habitats have attracted the attention of experts, environmentalists, researchers, academia, decision-makers, and the governments across the globe. It is imperative to examine and analyze the existing trends and themes in microplastic pollution-related research. It is also important to identify the most productive countries, organizations, and journals focusing on microplastic pollution and its impacts. The analysis is also needed to pinpoint the keywords and thematic evolution in research on microplastic along with the most influential and effective research in the area. This study serves this purpose. The study uses a systematic bibliometric approach to trace out the most productive countries, organizations, sources, and documents on microplastic related research. The study also provides detailed analyses regarding collaborations among countries and organizations in research on microplastic pollution. It also provides a detailed analysis of keywords and thematic evolution regarding microplastic research. This chapter also finds some emerging trends in research regarding the COVID-19 pandemic and microplastic pollution. This chapter pinpoints prospects of research on microplastic pollution and its implications on natural ecosystems, marine environment, human and nonhuman health, and approaches for the effective control and management of microplastic pollution. The conclusion of this analysis also stresses the need for collective strategies and frameworks to manage the microplastic pollution in the COVID-19 outbreak and post-pandemic world.