Emerging Contaminants in the Environment: Challenges and Sustainable Practices

Emerging Contaminants in the Environment: Challenges and Sustainable Practices covers all aspects of emerging contaminants in the environment, from basic understanding to different types of emerging contaminants and how these threaten organisms, their environmental fate studies, detection methods, and sustainable practices of dealing with contaminants. Emerging contaminant remediation is a pressing need due to the ever-increasing pollution in the environment, and it has gained a lot of scientific and public attention due to its high effectiveness and sustainability. The discussions in the book on the bioremediation of these contaminants are covered from the perspective of proven technologies and practices through case studies and real-world data. One of the main benefits of this book is that it summarizes future challenges and sustainable solutions. It can, therefore, become an effective guide to the elimination (through sustainable practices) of emerging contaminants. At the back of these explorations on sustainable bioremediation of emerging contaminants lies the set of 17 goals articulated by the United Nations in its 2030 Agenda for Sustainable Development, adopted by all its member states.

This book provides academics, researchers, students, and practitioners interested in the detection and elimination of emerging contaminants from the environment, with the latest advances by leading experts in emerging contaminants the field of environmental sciences.

• Covers most aspects of the most predominant emerging contaminants in the environment, including in soil, air, and water
• Describes the occurrence of these contaminants, the problems they cause, and the sustainable practices to deal with the contaminants
• Includes data from case studies to provide real-world examples of sustainable practices and emerging contaminant remediation

• Language: English
• Publisher: Elsevier Science
• Release date: Jan 8, 2022
• ISBN: 9780323859813

Book preview

Preface

Hemen Sarma, Delfina C. Domínguez and Wen-Yee Lee

The current book aims to shed new light on threats and problems caused by contaminants of emerging concern and understand sustainable remediation practices. Contaminants of emerging concern have a wide range of effects on human and animal health, disrupting various vital physiological functions such as reproductive failure, endocrine disruption, and cancer, as well as causing antibiotic resistance to pathogens, thereby putting human lives in danger. These emerging contaminants are a group of compounds not properly regulated and are constantly released from various sources of industrial and household applications. We aimed to bring together the most recent scientific research data on emerging contaminants in environmental sciences that have the potential for a sustainable future in this book. Thus this book can provide insights into these rapidly developing fields focusing on sustainable remediation technology. These green remediation systems, based on biological processes, are extremely beneficial and could be the next generation of technology for environmental applications involving the elimination of emerging contaminants.

The chapters in this book are written by eminent experts in the environmental and biomedical sciences. Contributing chapters will cover different aspects of emerging contaminants (including synthetic or naturally occurring chemicals, antibiotic-resistant microorganisms, pharmaceuticals, pesticides, industrial chemicals, surfactants, personal care products, endocrine-disrupting compounds, analgesics, antibiotics, antiinflammatory, and antidiabetic hormones) that are consistently found in soil and water. This book covers the causes and concerns of emerging contaminants, their detection, biological responses of living organisms, and sustainable practices. Even though nature can take care of resource recycling, remediation, and environmental rejuvenation, environmental contaminants beyond natural healing are currently a matter of serious concern. Some of the reasons for this disastrous situation are rapid population growth and industrialization, and the overuse of chemical compounds such as pesticides and antibiotics. Biotechnology and environmental chemistry have established green methods for monitoring and controlling emerging contaminants for a sustainable future. The chapters will discuss the basic concepts and efficiencies, waste disposal and by-product generation, current status of environmental issues, and the latest evidence-based approach to future applications and sustainable management of emerging pollutants.

The book is divided into 24 chapters written by 82 authors from leading international research organizations. The first chapter will examine the current state of emerging contaminants in soil and water, as well as integrated remediation approaches. Other chapters address the use of anticancer drugs in the environment; 1,4-dioxane and disinfection byproducts in water; the transport, fate, and bioavailability of emerging pollutants; pharmaceutical and personal care products; antimicrobial resistance in coastal waters; fate and transportation of perfluorinated compounds; engineered nanomaterials and their impacts, releases, and concentrations; plastic pollution in marine and freshwater environments; electronic waste as a new environmental contaminant; the effects of pesticides on human physiology, genetics, and evolution; nanoparticles' ecotoxicological effect; the QuEChERS method used to identify multiclass emerging contaminants, removal of quinolone antibiotics from wastewater and sewage sludge; chemosensing technology for rapid detection of emerging contaminants; bisphenol A detection methods; microalgae as whole-cell biosensors in the future; combinations of agricultural pesticides and their impact on populations and bioremediation strategies; assisted technology for the remediation of emerging contaminants, bioremediation of cytostatic pharmaceutical and personal care products, emerging technologies of antimicrobial resistance and removal in wastewater; and novel nanomaterials for the nanobioremediation of polyaromatic amines.

We hope to bring a holistic collection of knowledge to environmental science research scholars, engineering and biomedical scholars, graduate, and undergraduate students. We are confident that this book will provide valuable information to researchers and add a new dimension to the sustainable remediation approaches of emerging contaminants.

Chapter 1

Understanding emerging contaminants in soil and water: current perspectives on integrated remediation approaches

Hemen Sarma,    Department of Botany, Bodoland University, Rangalikhata, Deborgaon, Kokrajhar (BTR), India

Abstract

The volume of contaminated substrates (water, soil, and air) due to anthropogenic and technological sources has increased radically in today’s world. The environment is heavily polluted as a result of increased industrialization and natural resource extraction. A number of local, national, international, and intergovernmental environmental protection organizations are making policies to regulate emerging contaminants (ECs). The 2030 Agenda for sustainable development, which was adopted by all United Nations Member States in 2015, includes 17 sustainable development goals that urgently call to action all countries—developed and developing—to come together in a global partnership for the people of the planet. Thus every stakeholder must play an active role in its implementation. This is because contamination has become a challenge for environmental management today, necessitating the use of innovative and cost-effective measures. Many different strategies are being used to reduce pollution levels and for environmental cleanup. This chapter discusses processes that can contaminate soil and water from a variety of sources. Furthermore, various sources, categories, and their connections between biogeochemical transformations and the bioavailability of ECs in water and soil are discussed.

Keywords

Antibiotics; resistance gene; personal care products; pharmaceuticals; pesticides; bioremediation

List of abbreviations

ABZ Albendazole

ADD Androsta-1,4-diene-3,17-dione

ADs Anti-helminthic drugs

AED 4-androstene3,17-dione

ARGs Antibiotic resistance genes

ASWs Artificial sweeteners

BTEX Benzene, Toluene, Ethylbenzene and Xylenes

CBD Carbendazim

CWPO Catalytic wet peroxide oxidation

DBPs Disinfection by-products

DC Direct current

DDT Dichloro-diphenyl-trichloroethane

EKR Electrokinetic remediation

ECs Emerging contaminants

EDCs Endocrine disrupting compounds

ENMs Engineered nanomaterials

€ EURO

FEBA Febantel

FTACs Fluorotelomer acrylates

FTMACs Fluorotelomer methacrylates

FTOHs Fluorotelomer alcohols

HABs Harmful algal blooms

EC50 Half maximal effective concentration

HBCD Hexabromocyclododecane

LC50 Lethal Concentration 50%

LIBs Lithium-Ion Battery

LIBs Lithium-ion batteries

ML Macrolides

MAF-6 Metal-azolate framework-6

MP Methylparaben

MCs Microcystins

NF Nanofiltration

DEET N, N-diethyl-3-methylbenzamide

19-NTD 19-norethindrone

PFASs Perfluoroalkyl and polyfluoroalkyl substances

PFCs Perfluorinated compounds

PFCAs Perfluorinated carboxylic acids

PFOA Perfluorooctanoic acids

PFOS Perfluorooctane sulfonates

PFSAs Perfluorocarbon sulfonic acids

FOSAs Perfluorooctane sulfonamides

FOSEs Perfluorooctane sulfonamidoethanols

PFPAs Perfluorinated phosphonic acids

POPs Persistence organic contaminants

diPAPs Polyfluoroalkyl phosphoric acid diesters

PPCPs Pharmaceuticals and personal care products

PZQ Praziquantel

QNs Quinolones

RO Reverse osmosis

SAs Sulfonamides

SDGs Sustainable development goals

TCs Tetracyclines

TBBPA Tetrabromobisphenol A

TCS Triclosan

THMs Trihalomethanes

UHPLC-MS/MS Ultra-high efficiency chromatography-tandem mass spectrometry

USEPA United States environmental protection agency

UN United Nations

WTS Water treatment systems

WWTPs Wastewater treatment plants

1.1 Introduction

Pollution caused by human activities has had severe environmental consequences especially since the 20th century. The retaliation of nature against the attempts of humans to control it has manifested in the form of global warming, something that Bill McKibben foresaw in his book The End of Nature written three decades ago in 1990 (McKibben, 1990). The book contains McKibben’s apocalyptic vision of the impact of greenhouse gases on the earth’s climate which had invited the skepticism of many of his contemporaries. McKibben had pointed towards the pollution caused by humans as being responsible for irreversible changes in the environment. But what had seemed to be a remote possibility then has quickly transformed into a grim reality that we are now witnessing. Much like Rachel Carson’s Silent Spring (Sarma et al., 2016), McKibben’s book remains a prophetic reminder of the impact of pollution generated by human activities on nature in multiple ways and the life-threatening consequences of this not merely on the environment in general but on human beings themselves. Countless studies have been made since the last two decades of the 20th century on the nature of the pollutants contributing to the greenhouse effect, climate change and global warming. However, due to the drastic changes in technology and our lifestyles in the 21st century, studies since the last two decades have concentrated more on one particular category of environmental pollutants that are specific to the present-day world, viz., emerging contaminants (ECs), which can be seen in excessive amounts in soil and water ecosystems across the globe today.

ECs are major factors that jeopardize the well-being of the environment (Sanz-Prat et al., 2020). These include (1) pharmaceuticals and personal care products (PPCPs), (2) perfluorinated chemicals, (3) nanoparticles, (4) microplastics, (5) pesticides, (6) disinfectants, (7) antibiotics, (8) 1,4 dioxins, and (9) trihalomethane (Hu et al., 2019; Sharma et al., 2019). Various compounds, for example, PPCPs, are used to improve the quality of life and to treat diseases (Anim et al., 2020). However, the extreme environmental penetration and ubiquity of these contaminants into soil and water may pose a serious risk to public health and the environment. PPCPs may be defined as any substance used for personal health, cosmetic, or animal husbandry purposes (Ma et al., 2017). In 71 countries worldwide, environmental samples have identified the presence of 631 drug compounds and residues (Aus der Beek et al., 2016). A wide range of ECs have a critical impact on water resources (underground, drinking, and agricultural). Endocrine disrupting chemicals (EDCs) and pesticides have already been shown to have an effect on the quality of groundwater in pollution-prone areas (Sonne et al., 2018). These contaminants are usually present in easily detectable concentrations in drinking water, wastewater, and surface water (Islam et al., 2020a). For example, 113 PPCPs, 201 pesticides, and 56 industrial chemicals have been reported in surface water in Europe (Fang et al., 2019). This is due to the tremendous increase in PPCP production and use. The global pharmaceutical market grew by 3%–6% per year between 2018 and 2020. The budget for the Irish General Medical Services alone is projected to increase by 64% from EUR 1.1 billion in 2016 to EUR 1.8 billion by 2026 (Lenihan, 2015).

Little had been known earlier about the effects of drugs, steroids, antibiotics, and antibiotic resistance genes (ARGs) on our environment. These pollutants have been steadily released into the environment for a considerable period of time, but recent advances in technology and tools have made it possible only now to identify or detect these emerging environmental contaminants in soil and water (Szekeres et al., 2018). The detection of such pollutants in environmental components (water, wastewater, soil, and sediment) was a challenge given the complex nature of such pollutants and the difficulty of extracting such compounds from soil and water (Islam et al., 2020b). But with modern extraction techniques, together with improved sensitivity and precision of the instruments used for detection, it has become possible to quantify these contaminants accurately (Sarma et al., 2019b). The study indicates that ECs infiltrate through various sources into the soil and water systems, for example, industrial waste, municipal waste, household waste, pesticide applications, hospital waste, and pharmaceutical products (Stipaničev et al., 2017). These contaminants are absorbed by sediment, soil, water, surface water, and food chains. Figures show the various types and categories of contaminants entering water and soil ecosystems due to faulty treatment processes (Fig. 1.1). The literature on the sources, occurrences, environmental behavior, and fate of ECs is extensive (Nnadozie et al., 2017), but the path from sources to recipients remains an essential topic for advanced research.

Figure 1.1 Emerging contaminates from different sources to receptors.

Some of these ECs are eliminated by biotic interactions, but due to their persistence in nature, a significant amount of ECs are reported to be present in soil and water (He et al., 2018). ECs are not frequently regulated in the environment which makes it difficult to assess the nature and degree of their harmful effects on the survival of organisms in an accurate and consistent manner (Naidu et al., 2016). The sources of these ECs can increasingly be associated with recycling waste and wastewater (Fig. 1.2).

Figure 1.2 Recycling is the processing of used material into a new useful product. This is done to reduce the use of raw materials that would have been used otherwise. Various categories of ECs (a) are released to ecosystems in this process (b) that pose an ecological risk.

The environmental fate and transport of ECs in soil and water is a serious problem that can be seen through the increasing number of recent research publications about it. At present, experts are also looking for a more serious solution to overcome the toxicity of ECs that are frequently transported in soil and groundwater systems (González-Acevedo et al., 2019). Their existence in water and soil is frequently recorded (Liyanage & Walpita, 2020). Therefore effluent disposal and waste recycling must be monitored with a view to reducing environmental toxicity and ensuring the safety of the environment. The only options to reduce ecological risks could be sustainable remediation strategies for ECs (product disinfection, multidrug-resistant organisms, drug and pharmaceutical products, personal care products, and priority ECs) released from industrial, municipal, livestock manure, hospital and domestic wastewater (Liao & Chen, 2018). For details on current status, challenges and technological solutions, see Chapter 2, Emerging environmental contaminants – current status, challenges and technological solutions.

These contaminants harm soil and water ecosystems. Efforts have been made on a consistent basis to develop technologies for the remediation of ECs. The majority of ECs bioaccumulate in soil, water, air, and food. These ECs can be precipitated, concentrated, or immobilized to reduce their hazard using integrated remediation approaches for a more sustainable future. Microbial biofilms, for example, have been identified as a potential emerging bioremediation technology for many hazardous and toxic ECs such as EDCs and polyaromatic hydrocarbons. This chapter discusses a holistic approach to EC removal using such technologies. Furthermore, it is critical to comprehend how ECs’ mobility is managed and how it improves the quality of life of people. The United Nations (UN) adopted the sustainable development goals (SDGs) in 2015–17, goals aimed at providing society with a roadmap for transitioning from exploitation to sustainable utilization of our planet’s resources. A clean soil-water system is required for the majority of these SDGs. To reduce the environmental impact of ECs, with a greater emphasis on innovative and advanced monitoring, environmental and health pressures and risk monitoring, preventing and reducing contamination, tools and technologies are always welcome. As a result, the primary goal of this chapter is to understand ECs, categories and types, regulatory guidelines, and current perspectives on integrated remediation approaches.

1.2 Emerging pollutants in soil and water: categories and types

ECs are rather extended and comprise a wide range of chemical groups which can be divided into different categories of chemical pollutants (Daughton, 2016). A wide range of natural and synthetic chemical compounds are considered to be potential hazards, although not enough knowledge is available yet for all ECs (Fig. 1.3).

Figure 1.3 Single-use plastic enters both the soil and water ecosystems when disposed carelessly, causing environmental deterioration (a,c). Plastic particles spotted in an old drain (b).

ECs include perfluorinated compounds (PFCs), manufactured nanomaterials (NMs), agricultural chemicals, plastics (macro, micro, and nano), lithium and electronic waste, 1,4-dioxane, cyanotoxins, disinfection by-products (DBPs), antibiotic-resistant bacteria, cell-free antibiotic-resistant genes, environmental antibiotics, steroids, hormones, biocides, anthelmintic drugs (ADs), artificial sweeteners (ASW), and pharmaceutical drugs (Osama et al., 2021). Throughout the last two decades (1999–2009 and 2010–19), the prevalence of antibiotics in wastewater treatment plants (WWTPs) and in geographic areas (Europe, America, Asia, and Africa) has been summarized, analyzed, and evaluated (Wang et al., 2020a). For details of the composition, classification, and remediation of anticancer drugs in the environment, see Chapter 3, Anticancer drugs in the environment: Environmental levels and technological challenges.

Table 1.1 provides an overview of the different groups of pollutants considered to be ECs with examples. The compounds mentioned above are typical examples of emerging soil and surface water contaminants that have been present for a long time but have only recently been detected (Wang et al., 2019).

Table 1.1

In this context, the next few sections will discuss selected ECs of serious concern and important measures to combat / control ECs in the environment. Some case studies related to EC monitoring and analytical methods for detection, quantification, and sustainable remediation will also been highlighted.

1.2.1 Disinfection by-products: a hazard to public health

The process of disinfecting drinking water has led to major changes in public health since it was first used in the 20th century (Islam et al., 2020b). Clean drinking water has contributed to significant changes in general well-being. Ozonation and chlorination (Li, 2021) are widely used to clean water at present (Table 1.1). In the chlorination process, more DBPs are produced that could be hazardous when consumed. The formation of various DBPs and contaminants in 65 water treatment systems (WTS) across Canada has been evaluated by the National Disinfection Survey By-products and selected ECs (Tugulea et al., 2018). When the water is chlorinated, the organic matter in the water reacts with chlorine and the DBPs are produced. Triclosan is a common ingredient in soaps (0.10%–1.00%), shampoos, deodorants, toothpastes, mouthwashes, and cleaning supplies. A recent study demonstrates the toxicity and transformation properties of triclosan during ozonation and chlorination. The results showed that two hydroxylated by-products were formed during ozonation via nucleophilic substitution. Three chlorinated compounds were formed similarly through electrophilic substitution during chlorination. The toxicity results revealed that triclosan chlorination resulted in a 30-fold increase in anti-estrogenic activity due to the production of toxic polychlorinated transformation by-products (Li, 2021). DBPs are a major challenge in the treatment of drinking water (Yang et al., 2015). However, this reaction is based on several factors such as chlorine, bromine levels, type of treatment, pH, and temperature (Nieuwenhuijsen et al., 2000). In drinking water, at least 600 DBPs have been reported (Richardson et al., 2007). Haloacetic acids (HAAs) are one of the primary groups of DBPs and it is confirmed that the primary route of exposure to HAAs is through ingestion of chlorinated water. Similarly, volatile DBPs such as trihalomethanes (THMs) enter the bloodstream in high concentrations through the inhalation, ingestion, and absorption of chlorinated water in swimming pools (Whitaker et al., 2003; Yang et al., 2015).

The production of THMs in chlorinated water supply has been known for a long time. THMs are formed in water as chlorine reacts naturally with organic materials, particularly humic acids and fulvic acids. In 45 of 63 WTS across Canada, Iodo-THMs were detected. These THMs further produce chloroform (CHCl3) dichlorobromethane (CHCl2Br) and bromoform (CHBr3). THMs have received considerable attention because they produce animal carcinogenic chloroforms (Fayad, 1993; Simpson & Hayes, 1998). THMs are commonly detected in most WWTPs or chlorinated systems (Bellar et al., 1974). Clinical studies have shown a possible link between chlorination and DBPs that increase the risk of bladder and rectal cancer (Simpson & Hayes, 1998). In view of this significant health concern, a clean and DBP-free water treatment solution must be innovated in order to ensure a sustainable future. The release of wastes and wastewater from hospital, particularly those without adequate treatment, would expose people at risk of infection. In particular, it is important in the context of the 2019 Coronavirus Disease (COVID-19) pandemic in China to reduce health risks to the public and for the environment (Wang et al., 2020b).

1.2.2 Multidrug-resistant organisms

1.2.2.1 Antibiotic-resistant bacteria or cell-free genes resistant to antibiotics

Wastewater and WWTPs act as reservoirs of ARGs or bacterial reservoirs and are recognized as ARG suppliers of soil and water (Liao & Chen, 2018). They are also recognized as hotspots for horizontal gene transmission that allow ARGs to spread across bacterial stains. Mobile genetic components will probably play a key role in spreading antibiotic resistance in wastewater (Koch et al., 2021). Once ARGs successfully enter WWTPs, they may spread between endogenous bacteria and those passing through WWTP (Turolla et al., 2018). Wastewater also contains antibiotics, disinfectants, and metals; therefore frequent exposure to bacteria of these ECs can result in antibiotic, disinfectant, and metal resistance even at low concentrations (Montealegre et al., 2018). WWTPs do not work fully in removing these antibiotic-resistant bacteria and instead may actually spread them through their effluents into the environment (Wang et al., 2020a). However, the ARGs found in drinking water are difficult to identify for most economically marginalized countries because they not only need expensive equipment, but also incur high analytical costs. In recent times, various regions of the world have been found for containing a range of antibiotic-resistant bacteria in drinking water (Nnadozie et al., 2017). The drinking water samples tested by Ma et al. (2017) reported 84% higher levels of ARGs than natural sediment and soil. Acidovorax, Acinetobacter, Aeromonas, Methylobacterium, Mycobacterium, Polaromonas, and Pseudomonas were identified as the hosts for ARGs.

In addition, significant numbers of coliform bacteria, including Escherichia coli, with ARGs have been detected that could potentially put the health of community members at risk (Fernando et al., 2016). E. coli isolated from soil in Bangladesh turned out to be antibiotic resistant (Montealegre et al., 2018). The pathogenic E. coli isolated in this case was reported to be 42.3% resistant to at least one antibiotic, and 12.6% resistant to multiple antibiotics (three or more classes). In addition, a number of β-lactam AR genes (ARG, bla TEM, blaSHV, blaOXA, blaCTX-M) have also been identified in soil (Graham et al., 2016). These results suggest that ARGs contaminate a significant amount of soil and water and may be the primary source of large-scale human infection. While current data on integrated approaches to bioremediation provide useful information on the mitigation of pollution from ARGs, future studies are warranted to show a complete overview of the potential transfer of antimicrobial resistance from soil to agricultural products to human consumption and its associated health effects (Sun et al., 2020).

1.2.3 Drugs and pharmaceutical products

1.2.3.1 Environmental antibiotics: a major concern

Environmental antibiotics are a now a major concern for people around the world (Lin et al., 2020). In soil and aquatic environments, China has very high antibiotic detection rates, viz., 100%, 98.0%, and 96.4% for soil, surface water, and coastal water, respectively (Lyu et al., 2020). It is difficult to determine whether China’s high detection rate is due to its consumption or because it is a country dedicated to antibiotic detection research. Antibiotic use appears to be much higher in some parts of the world, indicating overuse, while it appears to be much lower in others, indicating a lack of access to these medicines. Antimicrobial consumption data are critical for countries to fully understand the trends and the amount of antibiotics used at a national level, which can inform policies, regulations, and interventions to optimize antibiotic use. The presence of several antibiotics in soil amended by poultry manure has been confirmed (Albero et al., 2018). Soil sample analysis showed that sulfamethoxazole, sulfamethazine, and lincomycin had high concentrations, while chlortetracycline, doxycycline, ciprofloxacin, and enrofloxacin were found to have very low (≤1.8%) rates. This finding shows, particularly regarding the availability of antibiotics, that the pathways of antibiotics entering soil via recycled water or manure can have a significant effect. The potential accumulation of antibiotics in vegetables exposed to low-dose contamination has also been investigated. For example, Brassica rapa subsp. has been evaluated (pak choi). The accumulation capacity of sulfamethoxypyridazin, tetracycline, ofloxacin, norfloxacin, and difloxacin has been assessed. Concentrations of tetracycline and difloxacin in the edible parts and roots were found to increase significantly over time, while concentrations of sulfamethoxypyridazine and ofloxacin increased slightly over time. The potential risk of antibiotics in vegetables to human health cannot be ignored (Yu et al., 2019).

Twenty-six antibiotics in four groups (acrolides, sulfonamides, tetracyclines, and penicillin) were reported in the drinking water catchment area of Northern Germany in 2016 (Burke et al., 2016). Similarly, in three major tributaries of the Liao River in Jilin province of northern China (Dong et al., 2016), seasonal and spatial variability of 12 antibiotics (sulfonamides[SAs], tetracyclines[TCs], macrolides[MLs], and quinolones[QNs]) was observed. Furthermore, QNs have been found most commonly in the sediments (1.34–8.69 ng g−1) and estuaries (0.99–10.86 ng g−1) of Yang River (Liu et al., 2020). The findings could provide an important idea of antibiotic contamination. It is accepted that antibiotic residues in soil, sediment, and water may pose potential health risks and their elimination is of the utmost importance. Therefore innovative techniques for the biodegradation of antibiotics and sustainable practices pertaining to this may not only help to control this situation, but also prevent potential health risks (Zhi et al., 2019; Azaroff et al., 2021; Koch et al., 2021). The dominant antibiotics found in surface water are the SAs, MLs, TCs and QNs, mainly attributed to the aquaculture and emission of domestic water (Lyu et al., 2020).

1.2.3.2 Environmentally activated steroid hormones

Steroid hormones have been identified as widespread in soil and water. They are considered to be contaminants and have adverse effects on aquatic organisms, animals, and humans (Song et al., 2018b). Chen et al. (2019) have identified steroid hormones (androsta-1,4-diene-3,17-dione[ADD], AED[4-androstene3,17-dione], 19-NTD[19-norethindrone]) and biocides (DEET[N,N-diethyl-3-methylbenzamide], TCS[triclosan], CBD[carbendazim], and MP[methylparaben]) in the environment. Steroid hormones were present at rates between 30.5 ± 1.25 and 105 ± 5.14 ng L−1 and biocides between 63.4 ± 2.85 and 515 ± 19.7 ng L−1, respectively. Similarly, three steroids—progesterone, androstenedione, and estrone—have been found to have relatively high soil concentrations of 109.7, 9.83, and 13.30 μg kg−1, respectively (Zhang et al., 2015). Physiologically and clinically, steroid hormones are classified as regulators of complex biological mechanisms, with significant effects on cellular growth, development, and physiology. The human body is also prone to excessive hormone exposure and/or ingestion. The presence of these steroid hormones in the soil therefore poses a significant life hazard for living organisms. Because of misuse of hormones and antibiotics in meat products, there have been serious concerns about the potential health risks (Wang et al., 2019).

1.2.3.3 Anthelmintic drug residues in water and soil

Anthelmintic drugs (ADs) are an important group of medicines that are frequently used to prevent and treat parasite infections in agriculture, aquaculture, and humans (Horvat et al., 2012). Some ADs have also been used to prevent pre- or post-harvest fungal infections of crops (Danaher et al., 2007). Even though the toxicity of ADs is considered quite safe for marine organisms, humans, and animals (Wagil et al., 2015), the ecological impact of ADs on the ecosystem remains uncertain. Few studies have documented the incidence and fate of ADs in at significantly lower rates than other pharmaceuticals product. Samples of surface water and soil in Chengdu, China, were found to contain 19 ADs in seven structural groups (benzimidazoles, diphenyl sulfides, imidazothiazols, hexahydropyrazines, macrocyclic lactones, salicylamilides, tetrahydropyrimidines). All ADs were detected in the environment at nanograms per liter levels (Li et al., 2020). The emergence of ADs in environmental media in a new field of research hence requires immediate attention to determine the impact of these drugs. Anthelmintic medicines [albendazol (ABZ), praziquantel (PZQ), febantel (FEBA)] may be removed from water with reverse osmosis (RO) and nanofiltration (NF) techniques (Dolar et al., 2012). For the purpose of determining the 19 ADs from the seven structural groups mentioned above, a sensitive method of quantification using pressurized fluid extraction and solid phase extraction, combined with ultra-high efficiency chromatography-tandem mass spectrometry (UHPLC-MS/MS), had to be developed (Li et al., 2020).

1.2.3.4 Presence of drugs and acids in water

The presence of drugs (associated with substance abuse) in drinking water was first described in 2008, about 12 years ago. The data that are available today in various cities in Europe, America, and Asia (Fig. 1.4) show that the problem is global (Santos et al., 2020). These substances go into the water cycle through sewage systems, and cities with insufficient wastewater treatment systems may have increased levels of illicit drugs in tap water (Davoli et al., 2019).

Figure 1.4 PPCPs have been polluting our water and soil. Their residue has been found in the soil and water, where it is responsible for the diseases. Photographed in Assam’s Sonitpur District’s Nameri National Park (a, b), in the foothills of the eastern Himalayas. Plastic pollution can be seen on the banks of the Kameng River (b, d), which originates in the eastern Himalayan mountains.

The existence of 21 pharmaceutical drugs, including illicit drugs, in wastewater, surface water, potable, water and sediment in the Turia River Basin (Valencia, Spain) has been reported (Carmona et al., 2014). In addition, using ultra-high-performance liquid chromatography coupled with tandem mass spectrometry (UHPLC-MS/MS), 47 contaminants were detected in fish, soils, and sediments in the Turia River (Carmona et al., 2017). All the compounds analyzed were detected and concentrated in wastewater > surface water > drinking water. PPCPs are dominated by ibuprofen, naproxen, and 11-nor-9-carboxy-to-tetrahydrocannabinol (THCOOH) with influences of up to 7.26 μg L−1. THCOOH, triclocarban, gemfibrozil, and diclofenac were the most common effluents in the range of 6.72–940 μg L−1. Similarly, diclofenac, gemfibrozil, ibuprofen, naproxen, and propylparaben have been detected very regularly in surface waters of the Turia River from low to 7 μg L−1. Significant concentrations of ibuprofen, naproxen, propyl paraben, and butyl paraben have also been found in mineral and tap water (approximately 100 μg L−1) (Carmona et al., 2014). WWTP wastes and untreated water discharged into the Turia River is a possible reason for the large number of PPCPs in its surface water and sediments. All of these PPCPs have a cumulative adverse effect on living organisms (Ghahari et al., 2021). While diclofenac was possibly the prime cause of the demise of entire vulture populations in India, it remains legally available in Italy and Spain, home to 90% of the vulture population in Europe. Certain countries like France have banned drug use and have helped protect vultures (Aus der Beek et al., 2016).

1.2.4 Personal care and other daily used product

1.2.4.1 Artificial sweeteners in water

Artificial sweeteners (ASW) are receiving a lot of attention recently due to their adverse effects (Song et al., 2018a). In general, non-nutritive ASW are known as persistent pollutants and are chemically stable in the environment. A total of 24 artificial sweetener detection tests have already been performed at 38 sites worldwide, including Europe, the United Kingdom, Canada, the United States, and Asia. The findings show that surface water, drinking water, ground water, seawater, rivers, and air contain non-nutritional, artificial sweetening products that are harmful to living species. The presence of saccharin and cyclamate in groundwater in Canada in 2011 has been reported (Van Stempvoort et al., 2011). Acesulfame, sucralose, cyclamate, and saccharine have consistently been found in Tianjin, China, ranging from 50 to 0.12 mg L−1 in surface waters, while acesulfame is dominant in surface and tap water. Aspartame was found at concentrations of up to 0.21 μg L−1 in all surface waters, but was not detected in groundwater and tap waters. Neotame and neohesperidine dihydrocalcones are ASW derived from citrus have been shown to be less frequent and have low concentrations (Gan et al., 2013). Since very limited studies have been carried out on ASW, it is difficult to conclude its impact on the environment. ASWs such as saccharin, acesulfame, and cyclamen were removed from water by synthesizing metal organic (metal-azolate framework-6 or MAF-6) derived porous carbons (Song et al., 2018a). The MDC prepared for 6 hours (MDC-6h) showed a remarkably high adsorption capacity, MDC-6h is therefore recommended for the extraction of ASW from water as an excellent adsorbent. In addition, zero-valent iron and biochar can be used for removing ASW (Liu et al., 2019).

1.2.4.2 Perfluorinated compounds in environment

Perfluorinated compounds (PFCs) are a wide range of compounds used in many applications, including clothing, stain-repellents, paper, additives, and aquatic film-forming foams (Deng et al., 2019). They are considered persistent, bioaccumulative, and toxic and have been found in environmental media. The most popular are (1) perfluorinated carboxylic acids (PFCAs), (2) perfluorocarbonsulfonic acids (PFSAs), (3) perfluorooctanoic acids (PFOA), (4) perfluorooctane sulfonates (PFOS), (5) fluorotelomer alcohols (FTOHs), (6) fluorotelomer methacrylates (FTMACs), (7) fluorotelomer acrylates (FTACs), (8) perfluorooctane sulfonamides (FOSAs), (9) perfluorooctane sulfonamidoethanols (FOSEs), (10) polyfluoroalkyl phosphoric acid diesters (diPAPs), and (11) perfluorinated phosphonic acids (PFPAs) (Corsini et al., 2014). Perfluoroalkyl and polyfluoroalkyl substances (PFASs) are a group of anthropogenic environmental pollutants that have received increased attention worldwide, as they are frequently found in aquatic environments, wildlife, and humans. Immunotoxic effects have already been reported for prenatal exposure to PFAS (Dalsager et al., 2016). Their potential toxicity to human health and ecological systems are a common concern for perfluorinated (PFCs) compounds in groundwater. PFCs in rivers can enter groundwater via riparian infiltration, potentially putting drinking water at risk and causing damage to the groundwater environment. In a city in northern China, from 2014 to 2017, 11 out of a total of 14 PFCs were detected in riverside groundwater (Liu et al., 2018). High-performance analysis was performed in tap water, 21 PFCs were detected in river water in southern China using supramolecular solvent-based microextraction coupled with HPLC-Orbitrap HRMS (Liang et al., 2020).

Since the 1950s a range of products have been developed that used PFCs such as PFOS and PFOA. These include non-stick kitchen utensils, water-proof textiles, protective layers for paper goods, food packaging, and tapestries. PFCs are a diverse group of chemicals made up of a partially or completely fluorinated alkyl chain (4–14 carbons) and are bound to different functional groups. PFCs include (1) carboxylic acids perfluoroalkyl (i.e., PFOA, PFDA), (2) perfluoroalkyl sulfonic acids (i.e., PFOS, PFBS), (3) perfluoroalkyl sulfonamides (i.e., PFOSA), and (4) fluorotelomer alcohols (i.e., fluorotelomer).

Food consumption tends to be the main contributor to the background level of PFC in human serum, while being exposed to contamination. PFCs are widely found in animal and human blood specimens (Suja et al., 2009). In the United States, the mean serum concentration of PFOS has been reported as 20.7 ng mL−1 and PFOA as 3.7 ng mL−1 for the general population. Children were found to have PFOS serum levels often greater than those in adults (Kato et al., 2009). The seemingly higher mean concentrations of PFCs in children than in adults was explained in terms of their higher exposure to PFCs, because of more frequent contact with carpeted floors and taped furniture, combined with hand-to-mouth touch behavior (Kato et al., 2009). Furthermore, in a study, the PFOA serum levels recorded in human blood ranged from 428 to 12,000 ng mL−1 and from 145 to 3490 ng mL−1 for PFOS (Olsen et al., 2007).

PFCAs and PFSAs have been shown to be persistent in nature, like their precursors. Some PFASs are identified to be harmful to humans and to animals (Borg et al., 2013). In addition, the most frequently detected PFAS—perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA)—are extremely mobile after infiltration into the aquatic environment. (Fujii et al., 2007). They are therefore extremely difficult to remove by conventional wastewater treatment (Filipovic et al., 2015). Clean water production is therefore a serious challenge (Yan et al., 2015). The interaction between PFCs and membranes is of major significance for the removal of PFCs through membrane separation, particularly in the adsorption on membrane interfaces and membrane rejection. NF membrane, and a tight NF membrane could therefore be used to remove PFCs (Li et al., 2021). For more details on environmental fate and transportation of PFCs, see Chapter 9, Environmental Fate and Transportation of Perfluorinated Compounds.

1.2.5 Priority emerging contaminants

1.2.5.1 Manufactured nanomaterials in soil environment

Nanotechnology has an enormous potential for scientific development (Borah et al. 2021a). In fact, several early and intensive efforts have been made to study the toxicology and health implications of NMs. Globally, the production and disposal of nanomaterials in the environment has increased overall (Gonçalves et al., 2019). The possible health effects of NMs cannot be neglected. The toxicity of NMs during a product life span from manufacture to disposal has to be examined (Zhang et al., 2019). There is currently no standardized experimental approach for quantifying the bioaccumulation potential of nanomaterials in general and in (benthic) invertebrates in particular. Recently the bioaccumulation ability of NMs in freshwater Hyalella azteca has been extensively evaluated (Kuehr et al., 2021). Nanomaterials, which are often toxic ions, may release toxins. Possibly the best-known examples are cadmium quantum dots that discharge cadmium ions (Kalinowska et al., 2018), silver nanoparticles that emit silver ions (McShan et al., 2014), and zinc oxide nanoparticles that are toxic mainly due to releases of zinc ions (Petrochenko et al., 2014).

Nanomaterials consist of chemically reactive groups on their surface that cause toxic effects (Fubini et al., 1995). In the case of crystalline silica, it remains unclear where certain chemical properties are critical to toxicity and where functional groups aiding the formation of free radicals are likely to be significant. Similarly, surfaces of nanomaterials could have catalytic properties that may cause numerous toxic effects. However, a unique design or modification of engineered nanomaterials (ENMs) may also reduce or increase the toxicity of the chemical product or combination. Therefore to some extent, these ENMs are harmful and environmental precautions should be taken during their application. Although ENMs have extensively transformed sectors like agriculture, among others, there has been growing concern for ENMs entering agricultural soil through biosolids, and its possible effects on agroecosystems (Chen et al., 2017). For details of ENMs and threats, releases and concentrations in the environment, see Chapter 10, Engineered Nanomaterials: Threats, Releases, and Concentrations in the Environment.

1.2.5.2 Agricultural chemicals/pesticides in the environment

The ecosystem may be vulnerable to mixtures of toxic pesticides (Odukkathil & Vasudevan, 2013). These mixtures are present in our food, water, and soil and can affect the health of humans and wildlife. The evidence that pesticides can become toxic in mixed products is increasing, a phenomenon called the cocktail effect. In view of human health and the environment, risk assessment of conventional synthetic pesticides is crucial (Nehra et al., 2021). Non-agricultural uses of pesticides in the United States are common and may therefore lead to the exposure of non-target ecosystems like urban waterways. However, exposure to the surface water resulting from the use of agricultural pesticides in recent decades has received considerably more attention (Stehle et al., 2019).

Pesticides are everywhere: in the air, water, and soil. Exposure to organophosphate pesticides has been identified in urine in children of 3–11 years of age living in agricultural and urban communities in Andalusia, Southern Spain. The exposure was thought to have been caused due to their diet, which included a large percentage of fruits, and not washing fruit prior to eating was considered to be the primary source of OP exposure (González-Alzaga et al., 2020). Another study examined the seasonal and occupational trends of 99 pesticides in house dust in Yakima, Washington, USA. Eighty-seven pesticides representing more than 28 classes were detected in house dust. The joint effects of ambient air pollution and agricultural pesticide exposures on the lung function of children with asthma cannot fully be ignored. However, the regulatory frameworks to protect us from pesticides require that specific chemicals and health tests are carried out on only one pesticide at a time. Pesticides occur in millions of different combinations and at varying concentrations in our food and environment. Children are particularly vulnerable to exposure to pesticides leading to adverse health effects (Bennett et al., 2019).

Therefore the only way to reduce the risk to health and the environment is to significantly reduce our overall use of pesticides and thus reduce our exposure to pesticides. Pesticide use is often necessary to meet the requirements for commercial crop quality and yield. However, the continued global use of pesticides poses potential risks to human and ecosystem health. This situation increases the urgency of developing nano-biotechnology-assisted pesticide formulations with high efficacy and low risk of adverse effects. Treatment of pesticide residues in the ecosystem through a number of processes such as biological and physicochemical degradation and advanced oxidation processes is also crucial (Nehra et al., 2021). For details of pesticide residues and their impact, see Chapter 13, Effects of Pesticides on Human Physiology, Genetics, and Evolution and Chapter 14, Integrative Behavioral and Ecotoxicological Effects of Nanoparticles.

1.2.5.3 Microplastics as contaminants in soil and aquatic systems

Plastic contamination is the accumulation of plastic products and microplastics in the atmosphere around the earth that adversely affects wildlife, wild animals, and humans, for example, plastic bottles, bags, and microbeads (He et al., 2018). In recent years, the increasing and prevalent presence of plastic pollution has attracted significant interest, especially toward small plastic particles (<5 mm) known as microplastics (Birch et al., 2020). Given numerous studies documenting the widespread presence of plastic waste in soil and water environments, work focuses on the presence and concentration of biological and chemical pollutants attached to plastic surfaces as well as potential pollutants. However no detailed studies on air and terrestrial microplastics have been conducted so far (Alimi et al., 2020). In seawater, hydrological forces like wind and waves can move marine fauna with plastic stuck to their bodies over long distances, extending the range of biological contaminants; several bryozoans, crustaceans, and molluscs have been found rafting in open sea litter (Kiessling et al., 2015). Therefore microplastics in water bodies are contaminant vectors and show the need for further research into this topic (Caruso, 2019). Given the tremendous quantity of litter and the persistence of plastic products in the world’s oceans, rafting dispersal can help invasive species spread. Plastic particle interactions with aquatic microbiota are a new challenge in research, particularly with respect to potential negative effects on microbial structure and microplastic metabolism (Caruso et al., 2018).

However, plastic debris can encourage adherence and colonization through the development of a biofilm through microbes that pioneer the development of plastisphere attachments (Zettler et al., 2013). Biofilm formation on the surface of microplastics can change the bioavailability of the same particulate matter. This was discussed by Kaiser et al. (2017), who showed that biofilms cause microplastic changes and promote sedimentation, especially in marine environments. There is an increasingly important ecological interaction between marine microorganisms and microplastics. The biggest threat to our Earth and the oceans is plastic pollution. Over the past 50 years, world plastics production is around 9.1 billion metric tons, with an annual rise of 8.7% (He et al., 2018). Many countries do not have a realistic plastics regulatory framework and therefore no accurate data is available. Although Africa is at the top of the list for plastic waste mismanagement, there is not enough data about microplastics and their interaction with other contaminants in its ecosystems (Alimi et al., 2020). In China, the abundance of microplastics in living organisms has been reported and compared to organisms in different parts of the world. The number of microplastic parts discovered in aquatic biota ranged from 0.07 to 164 individual particles in various organisms (Fu et al., 2020). Plastic remains a useful product but the proper recycling and disposal of plastic waste is important. Not only governments, but also consumers, play an important role in this respect. We urgently need uniform protocols, including the extraction and identification of microplastics. Main sources of microplastics in soil conditions include mulching film, sludge, irrigation, and atmospheric deposition (He et al., 2018). For details of plastic pollution in marine and freshwater environments, see Chapter 11, Plastic Pollution in Marine and Freshwater Environments: Abundance, Sources, and Mitigation.

1.2.5.4 Lithium as an emerging pollutant in soil

Energy is a requirement for electronic devices to operate. This is important in the current technological era. In electronic devices, the most used type of batteries currently is lithium-ion batteries (LIBs). However, these batteries are environmentally dangerous and are considered to be ECs (Robinson et al., 2018). Unscientific disposal of LIBs is the primary cause of lithium contamination of soil (Zeng et al., 2014). Lithium (Li) soil contamination is likely to increase as a result of its more widespread environmental dispersion, especially with regard to ubiquitous Li-ion batteries (Guo et al., 2016). For example, lithium concentrations in clay soil in New Zealand ranging from 0.08 to 92 mg kg−1 have been detected. Lithium is mobile in relation to other soil cations and can leach in water, to be ultimately absorbed by plants or other biological organisms. However, when Li+ is added to the soil, Li’s accumulation is limited, as Li is insoluble and therefore inaccessible to plants resulting in its limited phytoextraction. But at the same time, the accumulation of lithium begins to increase with an increase in soil pH. Plants, for example, accumulate Li without reducing biomass when soil pH is high and store it in leaves, seeds, and fruits (Robinson et al., 2018). These findings raise concerns regarding the potential risks when agricultural crops are grown near Li waste disposal sites. For more details of electronic waste an emerging contaminant in the geo-environment, see Chapter 12, Electronic Waste: An Emerging Contaminant in the Geo-Environment.

1.2.5.5 1,4-Dioxane in the water

1,4-Dioxane is a substance of growing environmental concern because of its abundance in surface waters worldwide, classified by the US-EPA as a class 2B carcinogen (Karges et al., 2020). This is a synthetic chemical used traditionally as a stabilizer in chlorinated solvents in industrial applications such as 1,1,1-trichloroethane (1,1,1-TCA). More recently, a number of synthetic chemicals are being used as solvents in paints, tints, antifreeze, body lotion, cleaning products, and perfumes. 1.4-Dioxane is also used in the formulation of pesticides, adhesives, and for the packaging of food. 1,4-Dioxane is widely distributed around the world with high mobility and durability. In the United States, the release of 1,4-dioxane into the environment is regulated only as industrial solvents when used as hazardous waste. Nevertheless, 1,4-dioxane present in additives, pesticides, and adhesives is not currently regulated. This regulatory limit has resulted in major environmental releases of approximately 617,000 pounds of solvent in 2017 (EPA 2017a; EPA 2018b). Over the last 40 years, 1,4-dioxane has been found in drinking water and remains unregulated, and recently analyzed data suggest that almost 30 million people in the United States receive 1,4-dioxane in drinking water above the permissible limit (0.35 μg L−1) (McElroy et al., 2019). Research in Germany has shown that 1,4-dioxane is already broadly distributed in rivers and can already be found at contamination sites in groundwater. Of 125 drinking water samples, 98 contained 0.034–2.05 μg L−1 of 1,4-dioxane (Karges et al., 2020).

Environmental concentrations of 1,4-dioxane have been observed at industrial groundwater sites with a significant human health concern (Adamson, Piña, & Cartwright, 2017). 1,4-Dioxane is a suspected carcinogen for human beings and an emerging contaminant found in surface water and groundwater resources (Melencion et al., 2017). Many conventional water treatment technologies for 1,4-dioxane removal are not effective due to their high water solubility and chemical stability (Myers et al., 2018). This chemical has been increasingly found in different locations in Japan, Korea, Canada, the United Kingdom, and the United States. More than one-fifth of the public water supplies in the United States contain detectable levels of 1.4-dioxane. Remediation efforts with common adsorption and membrane filtration techniques were not effective, emphasizing the need for alternative methods of removal (Godri Pollitt et al., 2019).

1,4-Dioxane affects not only human health but also all living organisms. The liver, kidneys, and eyes are mainly affected by the 1,4-dioxane (Dourson et al., 2017). Abiotic and bioaugmented granular activated carbon for the treatment of 1,4-dioxane-contaminated water has shown some hope of eliminating these ECs (Myers et al., 2018). For details of 1, 4-dioxane in the environment, see Chapter 4, Exposure to 1,4-dioxane and disinfection by-products due to re-use of wastewater.

1.2.5.6 Cyanotoxins in water

Cyanobacteria are naturally found in lakes, rivers, ponds, and other surface waters, also known as blue-green algae. If the right conditions exist, such as warm water with plenty of nutrients, they can quickly form harmful algal blooms (HABs). The blooms of the cyanobacteria producing toxins will increase as global temperatures increase (Manning & Nobles, 2017). Certain HABs produce toxins known as cyanotoxins, which can pose health risks to humans and animals with exposure to drinking water. In warmer and nutrient-rich environments, cyanobacteria typically thrive and can produce noxious HABs combined with powerful endotoxins and exotoxins. Cyanobacteria have more than 23 classes and 200 toxic metabolites (Manning & Nobles, 2017). Multi-residue Ultra Performance Liquid Chromatography-High resolution mass spectrometry is considered to be a reliable method for the detection of cyanotoxins and Di Pofi et al., has recently detected 21 cyanotoxins (including microcystins, cyanopeptolins, anabaenopeptins, and microginins) in surface water for human consumption in a volcanic lake in Viterbo (Lazio Region, Italy) during the period from January to March 2018 (Di Pofi et al., 2020). However, no research has been conducted on human skin interaction with cyanotoxins during water recreation, which causes adverse health effects (Nielsen & Jiang, 2020).

In the United States, a study of 1161 lakes and reservoirs showed predominant cyanotoxins. The mean concentration of 3.0 μg L−1 hepatotoxic microcystins (MCs) was evident in 32% of the lakes examined (Loftin et al., 2016). Many cyanotoxins, including cylindrospermopsin, neurotoxin saxitoxin, anatoxin-a, and nodularin-R, were also found in 4.0%, 7.7%, 15%, and 3.7% of the samples, respectively. However, given the widespread prevalence of MCs and other cyanotoxins, as well as the lack of accuracy across survey data, the effects of toxic algal blooms are still under consideration (Brooks et al., 2016). Widespread cyanotoxins that are highly harmful to drinking water (microcystins, cylindrospermopsin, anatoxin-a, and saxitos) can now be degraded using catalytic wet peroxide oxidation (CWPO) methods. This is supported by modified natural magnetite (Fe3O4-R400/H2O2) which is an affordable, simple, and environmentally friendly process for the removal of cyanotoxins (Munoz et al., 2019).

The emerging pollutants of concern are primarily synthetic chemicals, pesticides, drugs and personal care products, and hormones (Gavrilescu et al., 2015; Peng et al., 2018). Such pollutants may invade aquatic and soil ecosystems once they have been generated. Their fate and behavior are still not fully understood and their threats are not fully known in the soil and water environment. The elimination of emerging pollutants continues to pose a major challenge to the quality of water and soil (Beketov et al., 2013). As a result of rapid population growth and industrialization, the problems of emerging pollutants are increasing exponentially as waste material is discharged into the environment from homes, industries, hospitals and agriculture, contaminating water bodies, sediments, and soils (Lamastra et al., 2016). Proper regulatory frameworks are essential to solving these problems, such as emerging pollutants, fate and transport, treatment, and management. Scientific results and effects in these fields are not sufficient to help establish the right approaches. Water is essential for human life and anthropogenic activities can have a deep impact on the quality of water (Riva et al., 2018). Traditional pollutants and more than 700 emerging pollutants have infiltrated both terrestrial and marine ecosystems (Lamastra et al., 2016). For this reason, policymakers and scientists should work together to develop a sustainable remediation strategy for the future to address such a serious problem.

The ecological risks associated with ECs have gradually become visible (Jacob et al., 2021). Some coastal waters, like the Bohai Bay in China, face extreme pollution and large coastal waters are witnessing ecosystem disasters as water quality has deteriorated (Mao et al., 2019). The existence of multiple groups of ECs in 21 pools across Milan’s drinking water network has created risks to public health in the most populated and developed region of Italy (Riva et al., 2018). The most common compounds in raw surface water were 2,3,4-trichlorophenol (234TCP), 2,4-dimethylphenol (24DMP), and 4–nitrophenol (4NP), while 4NP and bisphenol A were found in treated water (BPA) (Ramos et al., 2021). The biomagnification of these compounds is quite obvious and difficult to check for infiltration into soil and water (Weber et al., 2010). The ECs were investigated and 56 compounds were detected in the basin waters of the two coastal Atlantic lagoons of Uruguay, South America, including five prohibited pesticides in the European Union: atrazine, carbendazim, chlorpyrifos ethyl, diazinon, and ethion (Griffero et al., 2019). A study found 13 ECs occurring in soil ecosystems in India: amoxicillin (AMX), bisphenol A (BPA), carbamazepine (CBZ), ciprofloxacin (CIP), dichlorodiphenyltrichloroethane (DDT), diclofenac (DCF), dimethyl phthalate (DMP), endosulfan (END), naproxen (NPX), nonylphenol (NP), norfloxacin (NOR), ofloxacin (OFL), and triclosan (TCS) (Visanji et al., 2018). Using this information, further analysis was carried out to record the elimination efficiency of these emerging pollutants in 42 wastewater treatment units. Similarly, agriculture pesticide levels in soil and wastewater irrigated crops have also been identified in Al Hayer (Saudi Arabia) for the assessment of potential ECs threats; pesticide levels in soil and agricultural products have been identified (Stehle & Schulz, 2015). ECs and associated human and ecological risks must be assessed in the water recycling system. In a study, 35 newly formed contaminants were detected in water reclamation and ecological reuse project (Lin et al., 2020). E-waste recycling workshops and adjacent open dumps in four metropolitan cities in India, namely, New Delhi (north), Kolkata (west), Mumbai (west), and Chennai (south) were examined on the surface of the soil. Average PAH (1259 ng g−1), PAE (396 ng g−1), BPA (140 ng g−1), and 1288 mg kg−1) concentrations were found at informal recycling sites. These parameters were higher than for dump sites, which showed PAH (1029 ng g−1), PAE (93 ng g−1), and BPA (121 and 675 mg kg−1) (Chakraborty et al., 2019). Informal e-waste recycling areas in Vietnam and Southeast Asia are still linked to environmental incidents and the adverse effects of the toxic substances involved. Surface soil and river sediment from rural villages with informal recycling activities in northern Vietnam were identified, showing the presence of unsubstituted and methylated PAHs (Hoa et al., 2020). Informal electronic waste recycling is also an emerging and ongoing source of persistent organic pollutants in the environment (Prithiviraj & Chakraborty, 2019).

The proper identification, detection and preparation of comprehensive lists of ECs is therefore important in order to for the UN SDGs to succeed. The UN SDGs have established the highest level of interdisciplinarity for pollution research. Several global issues are rapidly rising to the top of the agenda, all of which include the SDGs (https://sdgs.un.org/) that are related to soil and water quality issues such as (1) SDG 2, end hunger, achieve food security and improved nutrition, and promote sustainable agriculture; (2) SDG 3, ensure healthy lives and promote well-being for all at all ages (non-communicable diseases, mental health, and environmental risks); (3) SDG 6, ensure availability and sustainable management of water and sanitation for all; (4) SDG13, take urgent action to combat climate change and its impacts; (5) SDG 14, conserve and sustainably use the oceans, seas, and marine resources for sustainable development; and (6) SDG 15, protect, restore, and promote sustainable use of terrestrial ecosystems, sustainably manage forests, combat desertification, and halt and reverse land degradation and halt biodiversity loss (Sarma et al. 2008, Sarma et al. 2010). These SDGs are linked to specific soil and water science issues (Fig. 1.5), such as (1) sustainable food production, defined by proper nutrient management, reduces soil contamination, (SDG2 and SDG15); (2) addressing soil pollution issues caused by microplastics and ECs (SDG3); (3) improving water storage and filtering/buffering capacity (SDG6); (4) climate change (which may enhance carbon sequestration in soil and reduce nitrogen oxide emissions) (SDG13); and (5) the sustainable use of oceans and seas to reduce biodiversity loss (SDG 14 and 15).

Figure 1.5 Emerging contaminants have a significant impact on achieving the UNSDGs because they are linked to specific soil and water science issues, and thus every stakeholder must play an active role in its implementation.

Current research and the data collected until now will help provide proper knowledge of the physical and chemical interactions of ECs, their nature and transport to soil and water ecosystems and their biological consequences (Sanz-Prat et al., 2020). As of now, many monitoring tools and techniques have been developed that have a great potential for increasing confidence in the risk assessment of both regulated and emerging chemical pollutants (Gavrilescu et al., 2015). Persistent pollutants have been present in the environment for a very long time and are toxic if appropriate remedial approaches are not applied (Lin et al., 2020). Persistent and mobile pollutants pose a major and long-term threat to soil and groundwater health. Public health risks are well known and recognized for certain types of contaminants such as 1,4-dioxane, dibenzodioxin, furan, polychlorobiphenyl, and other persistent organic pollutants (POPs) (Miao et al., 2020; Verbrugge et al., 2018). It is a matter of concern that there is little awareness as yet of the serious health consequences of many of these pollutants (Simpson & Hayes, 1998). The fact that the impact of these pollutants is still unknown makes it much more difficult to predict the consequences. They may be toxic and mixed with other compounds. The results available till now are not well enough understood to present a clear picture of the future ramifications of the persistence of these pollutants in the environment. The effects of these contaminants in soil ecosystems require greater caution, particularly since soil plays an important role in combating climate change and the role of soil organisms in it (Biel-Maeso et al., 2017).

1.3 Regulatory guidelines

The existing environmental and soil restoration legislation for emerging pollutants should be enforced very carefully to achieve UN-SDGs (Mao et al., 2019). The US EPA has developed a White Paper on Aquatic Life Criteria for Emerging Concern Contaminants: Part I Challenges and Recommendations (US, EPA, 2020). A Contaminant Candidate List (CCL) was established in 1998 by the US Environmental Protection Agency (EPA) which includes chemicals that are unregulated, but which are known or expected to be contaminants in public drinking water (US, EPA, 2020). In this regard, the U.S. EPA has adopted a preventive approach for the screening of new chemicals and formulations and a method that is governed by the Safe Drinking Water Act. Every five years, a CCL will be published. This information is essential to implement UN SDGs 6 and 14 and to form a regulatory framework. In addition, a huge body of research data on ECs have been made available around the world in recent years, which can help solve the problem (Naidu et al., 2016).

In most economically marginalized countries, inadequate regulations and knowledge gaps of ECs lead to the causality dilemma of the chicken and the egg. Lack of knowledge