Plastic Pollution in Inland Waters – A Threat to Life

Abstract

This chapter explores a comprehensive approach to mitigating plastic pollution in freshwater ecosystems, aligning recommendations with the United Nations Sustainable Development Goals (SDGs). Regulatory measures, including extended producer responsibility and waste management infrastructure, are essential to curb plastic production. Mitigation strategies emphasize technological innovations, nature-based solutions, and individual actions. Education and outreach activities, targeting schools, communities, and businesses, play a pivotal role in preventing future pollution. Challenges and research needs highlight the evolving nature of the issue, necessitating a deeper understanding of plastic sources, long-term effects, and effective monitoring techniques. The interdisciplinary approach presented integrates environmental, social, and economic dimensions, emphasizing the interconnectedness of sustainability efforts.

1. Introduction

Inland waters refer to bodies of water that are not part of the ocean, including rivers, lakes, ponds, reservoirs, and wetlands [1]. These water systems play a crucial role in the Earth’s ecosystem and are of significant importance to both the environment and human societies [2, 3].

Inland waters support a diverse range of aquatic species, including fish, amphibians, insects, and plants. These ecosystems contribute to global biodiversity and provide habitat for many unique and often specialized species. They serve as a vital source of freshwater for human consumption, agriculture, and industrial processes. Rivers and lakes are important reservoirs that store and supply water for various uses, sustaining human life and economic activities [4].

Inland waters provide a variety of ecosystem services, such as water purification, nutrient cycling, and flood control. Wetlands, for example, act as natural filters, improving water quality by trapping pollutants and sediments [5]. Lakes and rivers offer recreational opportunities such as boating, fishing, swimming, and wildlife observation. These activities contribute to the tourism industry and provide social and economic benefits to local communities [6].

Historically, rivers and lakes have been essential for transportation. Even today, many rivers are used for shipping goods, and lakes provide important navigation routes. Inland waters are crucial for agriculture, providing water for irrigation. Many civilizations throughout history have flourished near rivers and lakes due to the availability of water for farming. Rivers are often harnessed for hydropower generation, providing a renewable and relatively clean source of energy. Dams and reservoirs are constructed to regulate water flow and generate electricity [7].

Inland waters play a role in climate regulation by influencing local weather patterns and helping to moderate temperature extremes. They can also act as carbon sinks, sequestering carbon and mitigating climate change. They often hold cultural and spiritual significance for communities. Many societies have developed around rivers and lakes, and these water bodies are integral to their myths, traditions, and rituals. Inland waters are considered biodiversity hotspots, with high concentrations of unique species. Protecting these ecosystems is crucial for maintaining overall global biodiversity [5].

2. From miracle material to global menace: Plastics’ rise and fall

The world is draped in plastic. From the clothes we wear to the toys our children play with, from the food we eat to the bottles we sip from, plastic has become omnipresent, infiltrating every facet of our lives. What began as a revolutionary invention in the early 1900s has morphed into a ubiquitous material fuelling a “use and throw” culture with dire environmental consequences [8, 9].

Plastics boast remarkable properties – lightweight, durable, and affordable. These advantages propel them into everything from packaging to furniture, medical equipment to cleaning products. They have revolutionized industries, streamlined transportation, and offered countless conveniences. Yet, the very qualities that make plastics so useful also contribute to their sinister side. Their resistance to degradation, once a marvel, translates to an alarming reality – they persist in the environment for centuries [10].

Landfills groan under the weight of discarded plastic, while oceans choke on an endless tide of plastic debris. Microplastics, insidious fragments born from larger plastic breakdown, infiltrate food chains, poisoning ecosystems and potentially endangering human health. The statistics are staggering: millions of tonnes of plastic waste dumped annually, plastic pollution threatening countless species, and a growing plastic island swirling in the Pacific Ocean [10, 11].

The convenience plastic offers comes at a steep price. Our addiction to this ubiquitous material has unleashed a global pollution crisis. But, amidst the devastation, glimmers of hope emerge. Innovative minds are developing biodegradable alternatives, exploring plastic recycling methods, and promoting responsible consumption habits. Governments are implementing stricter regulations to curb plastic production and encourage better waste management.

The challenge we face is monumental but not insurmountable. We must transition from a disposable mindset to one of responsible stewardship. Investing in sustainable alternatives, embracing reuse and repair, and actively seeking solutions to manage existing plastic waste are crucial steps on this path. By rethinking our relationship with this ubiquitous material, we can rewrite the narrative of plastic, transforming it from a global menace back into a force for good [12, 13, 14].

2.1 Beyond the blue bin: Unveiling the hidden sources of plastic pollution

2.1.1 Human reliance on single-use plastics

Single-use plastics like bottles, bags, straws, and food packaging offer ease and convenience, contributing to their popularity. The cheap production cost of these plastics makes them readily available and tempting to manufacturers and consumers. Many people underestimate the far-reaching consequences of discarding single-use plastics after a single use [15].

2.1.2 Inadequate waste management

Many countries lack proper waste collection and disposal systems, leading to plastic ending up in landfills, waterways, and the environment. Practices like open dumping and burning of plastic waste release harmful toxins and microplastics into the air and soil. Even in developed countries, recycling capacity for certain types of plastic is limited, and recycled content in new products remains low [15, 16].

2.1.3 Unregulated industrial practices

Microfibers from synthetic clothing, beads in personal care products like scrubs, and pre-production pellets all contribute to microplastic pollution. Production and transportation of plastic materials can lead to accidental spills and the release of microplastics. Lost or discarded fishing gear, primarily made of plastic, constitutes a significant source of water pollution [16].

2.1.4 Consumer choices

Our preference for readily available and disposable products fuels the production and use of single-use plastics. We prefer “convenient” over sustainability. Lack of awareness about the lifecycle of plastic and its environmental impact can lead to irresponsible disposal practices. Availability and affordability of sustainable alternatives to plastic products sometimes remain a challenge (Figure 1) [16, 17].

Figure 1.

Classification of plastic materials. Adapted from: https://www.plasticsforchange.org/blog/different-types-of-plastic.

2.2 Unraveling the web of plastic pollution in inland waters

2.2.1 Invisible menace

The silent tide of plastic pollution has swept inland, infiltrating our rivers, lakes, and freshwater ecosystems. This insidious threat emerges from diverse sources, weaving a complex web of contamination [2, 18].

2.2.2 Micro mania

Microplastics, tiny warriors less than 5 mm in size, dominate the battlefield. Some emerge preformed, shed from cosmetics, textiles, and even fishing nets. Others are battle-hardened veterans, broken down from larger plastic warriors like bottles, their resilience a curse that allows them to linger for centuries. Research tells us these seasoned veterans, the secondary microplastics, outnumber their younger counterparts [19].

2.2.3 Transformation’s dance

The fate of these microplastic warriors is a complex ballet. They migrate from manufacturing to consumption, then discard, only to return in an intricate circle back to human society. Within inland waters, they undergo a five-act transformation: suspended pieces, settling sediments, resuspended nomads, buried soldiers, and finally, travelers to the marine world. This intricate dance with the environment allows them to entangle aquatic plants, be ingested by unsuspecting organisms, and ultimately impact us all [19, 20, 21].

2.2.4 Agricultural echoes

Beyond the direct battlefield, agriculture plays a subtle role. Millions of tonnes of sewage sludge containing microplastics are used to nourish land, while discarded agricultural films leave their plastic ghost behind. Even irrigation water, tainted with these tiny warriors, carries the pollution further, contaminating soil and eventually seeping into freshwater bodies [21].

2.2.5 Rain’s downpour

From the heavens above, another enemy arrives. Rainfall-runoff and atmospheric deposition, like silent assassins, carry pollutants, including plastics, directly into vulnerable small water bodies. Mismanagement and negligence become accomplices, further bolstering the enemy’s ranks [22].

2.2.6 Macroplastics and megaplastics

This web also ensnares larger warriors. Macroplastics, visible to the naked eye, litter riverbanks and lake beds, while megaplastics, giants from the seas and landfills, cast their long shadows. Mismanaged waste, individual carelessness, and industrial leaks all feed the ranks of these visible enemies. Wind, surface runoff, and the very flow of rivers become their chariots, spreading their dominion further. Despite the initial focus on plastic pollution being due to these types of plastic, recent research has not given them much attention [18, 22, 23, 24].

Understanding the multifaceted nature of plastic pollution in inland waters is crucial for crafting effective solutions. By recognizing the diverse sources, the dance of transformation, and the silent allies like rain and agriculture, we can begin to untangle this complex web and protect our precious freshwater ecosystems.

3. Freshwater ecosystems: choking on plastic’s grip

The crystal-clear image of a serene lake belies a harsh reality – freshwater ecosystems are drowning in plastic. This global environmental crisis is not just confined to the oceans; it is plaguing rivers, lakes, and wetlands at an alarming rate [25, 26, 27, 28, 29].

3.1 Biodiversity under siege

The very fabric of freshwater life is unraveling under the onslaught of plastic. Studies reveal over 206 freshwater species, from tiny invertebrates to majestic mammals, bearing the scars of plastic ingestion [25]. Entangled limbs, choked intestines, and internal injuries – the plastic menace mimics its marine counterpart in inflicting a gruesome toll on freshwater fauna [26].

3.2 A toxic cocktail

Beyond physical harm, plastic acts as a Trojan horse, transporting a chemical cocktail into the bodies of aquatic life. These additives and waterborne pollutants can wreak havoc, triggering reproductive problems, growth abnormalities, and even altering organ function [28].

3.3 Ecosystems on edge

Plastic disrupts the delicate dance of life in freshwater ecosystems. It smothers habitats, alters water flow, and hinders natural processes, leaving these vital systems crippled in the face of climate change. Ultimately, the consequences ripple outwards, impacting millions of people’s livelihoods, food security, and well-being [29].

3.4 Plankton in peril

Microplastics are not just an eyesore; they pose a grave threat to the ecosystem’s silent workhorses – plankton. These microscopic organisms, crucial for carbon sequestration and ecosystem health, are being adversely affected by the plastic invasion, jeopardizing the planet’s ability to combat climate change [27].

3.5 Cascading consequences

The boundaries between ecosystems are blurry. Plastic pollution in one system does not stay put; it cascades through interconnected webs, impacting terrestrial, aquatic, and marine realms alike [27]. From land-based sources, plastic contaminates rivers and wetlands, eventually finding its way to the depths of the ocean, leaving no corner untouched.

The plastic pandemic in freshwater ecosystems demands immediate and coordinated action. Robust recycling programs, responsible disposal habits, stringent legislation, regular inspections, and replacing synthetic polymers with eco-friendly alternatives are all crucial steps in this fight. We must not underestimate the severity of this crisis; the situation in freshwater may be as dire as in the oceans, yet it remains largely under-recognized [25].

Only by acknowledging the full scope of this plastic chokehold and taking decisive action can we hope to heal our freshwater ecosystems and restore the delicate balance of life they sustain.

4. Microplastics and nanoplastics: a tangled web of human health threats

Microplastics, minuscule invaders less than 5 millimeters in size, and their even tinier cousins, nanoplastics, are silently pervading our world. We breathe them in the air, drink them in our water, and eat them in our food. This pervasive presence ignites a crucial question: What are the potential impacts of these minuscule menaces on human health and society?

4.1 Ingestion pathways

Our food and water, the very sustenance of life, become unwitting Trojan horses for these plastic particles. Seafood, drinking water, and even the air we breathe are increasingly contaminated [30, 31, 32, 33, 34, 35, 36]. This alarming reality suggests a silent invasion, with microplastics insinuating themselves into our very bodies.

4.2 Tissue presence

The grim reality is not limited to external exposure. Recent studies have unearthed microplastics within human tissues, including the gastrointestinal tract, placenta and breast milk [37, 38, 39, 40]. While the full implications remain unclear, this discovery sends shivers down the spine, raising potent questions about their potential to harm us from within.

4.3 Bioaccumulation concerns

Could these plastic infiltrators become unwanted tenants in our bodies? Evidence suggests the chilling possibility of bioaccumulation, where microplastics build up in the food chain, eventually reaching our plates. The extent and health effects of this phenomenon are still unfolding, but the potential implications are far-reaching [41, 42, 43, 44].

4.4 Potential for physical harm

The mere size of these invaders raises concerns. Microplastics, like silent saboteurs, could cause physical harm due to their ability to accumulate in tissues. Studies hint at inflammation, oxidative stress, and even disruptions in nutrient absorption and the gut microbiome, a vital ecosystem within us [41, 42, 43, 44].

4.5 Toxicological threats

Microplastics are not just inert trespassers; they can act as sponges, adsorbing and concentrating environmental pollutants. When ingested, these pollutants are released within our bodies, raising alarms about potential toxicological effects [42, 45]. This adds another layer of complexity to the already murky picture of their impact.

4.6 Inflammatory responses

Beyond physical harm, some research suggests that microplastics can trigger unwelcome guests in the form of inflammatory responses and immunological reactions [46, 47, 48]. While the long-term consequences remain obscured, the possibility of internal battles against these invaders is unsettling.

4.7 Unraveling the web of uncertainty

Our understanding of microplastics and nanoplastics and their impact on human health is like a half-woven tapestry. We see glimpses of potential harm – physical disruption, internal battles, and toxic cocktail delivery – but the full picture remains veiled. More research is urgently needed to untangle this web of uncertainty and assess the true scope of the threat these tiny trespassers pose. While answers remain elusive, one thing is clear: inaction is not an option. We must prioritize research, implement preventive measures to curb plastic pollution, and develop strategies to mitigate the potential risks. The health of future generations and the integrity of our ecosystems depend on it.

5. Microplastics and human health: future trends and research focus

5.1 Expanding research efforts

The field of microplastics and human health is anticipated to see a surge in research efforts aimed at understanding the sources, pathways, and potential health effects of microplastics [49, 50, 51]. With the rapid advancement in analytical techniques, our ability to detect and quantify microplastics in various biological samples is expected to improve. This will provide more accurate data, thereby enhancing our understanding of the extent and implications of microplastic pollution [52, 53].

5.2 Standardization of methods

There is a growing need for standardized methods to measure and characterize microplastics in human tissues. The development of consistent methodologies will enhance the comparability of studies and contribute to a more comprehensive understanding of exposure levels. This is crucial for establishing reliable baselines and tracking trends over time [52, 53, 54].

5.3 Long-term health studies

Future research may involve more longitudinal studies to assess the long-term health effects of microplastic exposure. This includes investigating chronic exposure scenarios and potential cumulative impacts. Such studies are critical for understanding the potential health risks associated with prolonged exposure to microplastics [41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53].

5.4 Regulatory considerations/actions

As awareness of the potential impacts of microplastic pollution on human health grows, there may be increased attention from regulatory bodies. This could lead to the development of guidelines or regulations to mitigate exposure. Such measures are essential for protecting public health and preventing further environmental degradation [55, 56, 57].

5.5 Technological innovations/advances

Advances in analytical techniques and technologies may enhance our ability to detect and characterize microplastics, including nanoplastics, in various matrices. This will allow for more accurate risk assessments and inform mitigation strategies [58, 59, 60]. The integration of artificial intelligence in microplastic research is also a promising trend, offering new possibilities for data analysis and interpretation [58].

In conclusion, the field of microplastics and human health is poised for significant advancements in the coming years. Through expanding research efforts, standardization of methods, long-term health studies, regulatory actions, and technological innovations, we can gain a deeper understanding of this global issue and develop effective strategies to mitigate its impacts.

6. The impact of micro and nanoplastics on aquatic life in freshwater ecosystems

This segment explores the impact of microplastic and nanoplastic on organisms residing in freshwater ecosystems, including plants, animals, and microbes. Ongoing research in these domains is essential, as much more investigation is required to fully comprehend the situation and understand how organisms respond to plastic pollution.

6.1 The growing threat to freshwater flora

The menace of plastic pollution poses an escalating threat to freshwater flora, impacting the lifeblood of aquatic ecosystems worldwide. The infiltration of microplastics and nanoplastics, derived from larger debris and everyday products, has become pervasive in lakes, rivers, and wetlands, posing multifaceted dangers to aquatic plants. Studies on duckweed and water hyacinths reveal the physical harm inflicted by sharp plastic fragments, causing lacerations and punctures on delicate photosynthetic tissues [61, 62, 63]. These injuries compromise plant vigor and productivity. Additionally, nanoparticles create a coating on biofilm surfaces, potentially impeding algal growth [64].

The obstruction of sunlight, essential for photosynthesis, emerges as a significant concern, with nanoplastics lingering in the water column, creating a haze that obstructs sunlight penetration [65]. This plastic-induced shade suppresses the growth of submerged plants, hindering their capacity to fix carbon and maintain biomass. Ingestion of microplastics further intensifies the threat, with studies reporting accumulation on and within plant tissues, raising concerns about enzyme inhibition, cell stress, and metabolic decline [66, 67].

Plastics’ role as carriers of harmful chemicals and sponges for waterborne pollutants exacerbates the problem. Common additives like phthalates and flame retardants, confirmed endocrine disruptors, leach into the water from plastics, while organic contaminants like Polychlorinated Biphenyls (PCBs) and pesticides readily bind to plastic surfaces, heightening plant exposure to toxins [68]. Documented impacts include altered cell structures, disrupted pigment production, and weakened enzymatic activity [67].

In the genus Lemna, crucial as bioindicators and base feeders in aquatic food webs, exposure to microplastics leads to stunted growth, diminished pigmentation, and cellular membrane disruption [69]. Further concerns arise as research indicates microplastics may enhance metal bioaccumulation in water hyacinths, potentially promoting the spread of invasive plants in disturbed ecosystems [70, 71].

The comprehensive understanding of plastic’s impact on freshwater flora is still unfolding, yet existing evidence paints a dire picture. From physical harm to chemical threats, aquatic plants globally demonstrate vulnerability to this pervasive pollution. Safeguarding freshwater ecosystems demands concerted efforts to curtail plastic releases, improve waste management, and advance biodegradable alternatives. Urgent research extending beyond lab studies is crucial to quantifying impacts on natural plant communities.

6.2 Menacing consequences for freshwater fauna

Freshwater ecosystems, vital conduits of life for numerous species, face a formidable adversary – plastic pollution. Microplastics and nanoplastics, minute fragments originating from larger debris and everyday items, now extensively taint rivers, lakes, and streams worldwide. This pervasive menace poses a myriad of challenges for our freshwater fauna.

Ingestion stands out as a major concern, as a diverse array of animals mistakenly consume microplastics, leading to false satiety, nutrient dilution, and potentially fatal blockages. Research, such as a study on Great Lakes fish, reveals that over 80% of them have microplastics in their guts [72, 73]. Ingestion not only hampers growth and reproduction across various species, from zooplankton to fish [74].

Entanglement introduces another layer of peril. Abandoned fishing gear, packaging bands, and other plastic debris ensnare and fatally harm turtles, waterfowl, fish, and more [75, 76]. Apart from causing drowning or strangulation, entanglement inflicts severe injuries, impeding mobility and escalating predation risk.

Plastic debris also acts as a Trojan horse for invasive species and toxins. Microplastics readily absorb pollutants and pathogens, subsequently delivering them to animal tissues upon ingestion [77]. Studies confirm the transfer of heavy metals, petroleum compounds, and other harmful chemicals from plastics to organisms [78]. Furthermore, floating plastic serves as a habitat for invasive species, facilitating their spread [79].

Beyond these documented effects, plastic disrupts natural behaviors like algal grazing and can alter endocrine systems and respiration [80, 81]. The full picture of chronic plastic exposure remains under investigation, but the combined physical and chemical threats are incontrovertible.

Specific instances illustrate a grim reality. Perch larvae exposed to microplastics experience a 40% mortality rate within days [82]. Over half of Asian carp in Illinois rivers harbor nanoplastics [83]. Plastic ingestion by freshwater birds mirrors the devastating impacts observed in their marine counterparts [84].

Even iconic species like river turtles are not immune. More than 50 freshwater turtle species have been documented ingesting or entangling themselves in plastic [76]. For these long-lived reptiles, plastic accumulation can lead to severe health decline over decades, compounding the threats to their already endangered status.

The sheer volume of plastic infiltrating freshwater systems poses a dire threat to biodiversity and ecosystem health. With plastic production expected to surge, immediate action is imperative. Stricter policies, enhanced waste management infrastructure, widespread education on proper disposal and alternatives, and ongoing research on plastic impacts and mitigation are essential (Figure 2) [85, 86].

Figure 2.

Consequences of plastic pollution for aquatic life.

6.3 Microbial battleground: plastic’s covert assault on freshwater ecosystems

Freshwater ecosystems, the concealed engines of life, confront an imperceptible adversary: plastic pollution. Microplastics and nanoplastics, minute remnants from larger debris and daily items, now cover lake bottoms and riverbeds. Yet, this intrusion is not merely passive; it actively reshapes the unseen realm of freshwater microbes in intricate and unsettling ways.

Plastics create new habitats for certain bacteria, fostering adaptations like hydrocarbon degradation and specialized “grappling hooks.” Genera such as Pseudomonas, Bacillus, and Vibrio dominate these “plastispheres,” showcasing remarkable adjustments to their plastic environments [86, 87]. While the overall impact on ecosystem function remains uncertain, it is clear that plastics instigate novel microbial relationships.

However, this apparent symbiosis has a sinister side. Plastics function as carriers for disease-spreading, with pathogenic bacteria like Vibrio cholera, Legionella, and Pseudomonas aeruginosa exploiting these platforms for accelerated dispersal [88, 89]. This disturbing trend suggests that plastic pollution may be facilitating the swift spread of harmful microbes in freshwater systems.

The narrative extends further. The intense competition on plastics initiates an evolutionary arms race among bacteria, promoting the emergence of more virulent strains through toxin and antibiotic release [90, 91]. Plastic additives like flame retardants and Bisphenol A (BPA) contribute to this selection pressure, potentially elevating mutation rates and genetic adaptation [92]. In essence, plastic pollution favors the development of hardier, more harmful microbes in freshwater.

Beyond targeting specific species, plastic disrupts microbial diversity at its core. Studies comparing pristine and plastic-laden sediments reveal significant declines in community richness and evenness [93, 94]. This imbalance could have cascading effects, disrupting the crucial roles played by sediment bacteria in nutrient cycling and aquifer health.

Moreover, plastics release a toxic blend of chemicals, including monomers, stabilizers, and pesticides, potent enough to hinder microbial growth at environmentally relevant concentrations [77]. UV-degraded plastics release even more hazardous derivatives, intensifying chemical warfare in an already hostile environment [95].

The threat transcends surface contamination. Vertical transport of microplastics into sediments endangers vital communities responsible for bioremediation and nutrient cycling. N-cycling bacteria and sulfur-oxidizing populations, crucial for water decontamination, are impacted by plastics [96, 97]. This unseen battleground beneath the surface underscores the profound impact plastics have on the foundational elements of freshwater ecosystems.

Adding to the complexity, invasive aquatic plants may benefit from plastic pollution, as debris offers new habitats and microplastics enhance biofilm formation, potentially providing protection from pollutants [79, 98]. This alliance between plastic and invaders may accelerate the spread of undesirable species in waterways.

Finally, plastic fragments infiltrate the sensitive hyporheic zone, the crucial meeting point of groundwater and surface water with unique microbial communities. Significant differences in microbial biodiversity are observed between plastic-contaminated and pristine hyporheic zones, raising concerns about plastic’s influence on these critical life support systems.

In conclusion, plastic pollution poses a disconcerting threat to freshwater microbes. While some may flourish on plastic islands, the larger ecosystem bears the brunt of the impact. Reduced diversity, toxic leaching, disrupted biogeochemical services, and the rise of potentially dangerous bacterial strains are alarming consequences.

The future of our freshwater systems, and ultimately our own well-being, hinges on safeguarding these microscopic life forms. Neglecting the hidden world of microbes would be akin to ignoring the very roots of a tree. Let us act now to ensure these vital communities thrive, preserving the health and resilience of our freshwater ecosystems for generations to come.

7. Regulatory and mitigatory measures: a comprehensive approach to plastic pollution

This section is not just a laundry list of Sustainable Development Goals (SDGs) – it is a battle cry. For over 30 years, we have danced around the fringes of reducing, reusing, and recycling plastics. The Earth is at a breaking point, and we cannot waltz our way out anymore. We need to link these actions directly to the SDGs, transforming them into potent weapons against plastic pollution. The time for talk is over; the time for strategic action is now.

Curbing plastic pollution demands a three-pronged attack: stricter regulations, innovative mitigation strategies, and empowered individuals. Linking these efforts to the UN’s Sustainable Development Goals (SDGs) offers a roadmap for lasting change. Governments and NGOs are already leading the charge with awareness campaigns and initiatives to curb plastic use. By anchoring the fight within the SDG framework, we gain a shared understanding and a springboard for effective action [99, 100, 101, 102, 103, 104, 105, 106, 107].

7.1 Regulatory and policy measures

Our insatiable appetite for convenience has fuelled a global plastic crisis. We churn through 300 million tonnes of plastic annually, half of it disposable, creating a staggering waste stream roughly equivalent to the weight of humanity itself. This plastic tide pollutes ecosystems, endangers marine life, and even infiltrates our food chain. Recognizing the urgency, governments worldwide are stepping up with regulatory measures linked to the UN Sustainable Development Goals (SDGs):

7.1.1 SDG 14: life below water – regulating plastic production

Countries like Rwanda and Kenya are leading the charge with bans on specific single-use items like bags and straws. The EU has followed suit, and India recently enacted a comprehensive ban targeting various disposable plastics. This aligns with SDG 14’s call to “conserve and sustainably use the oceans and marine resources” [99, 102].

7.1.2 SDG 12: responsible consumption and production – extended producer responsibility (EPR)

France’s heavy levies on plastic packaging producers exemplify EPR policies aimed at shifting responsibility to manufacturers, encouraging them to design for reusability and recyclability. This echoes SDG 12’s focus on “promoting sustainable production and consumption patterns” [108, 109].

7.1.3 SDG 15: life on land – protecting ecosystems

Establishing and enforcing protected areas, as Bangladesh is doing with international support, safeguards ecosystems from plastic pollution. This aligns with SDG 15’s goal of “protecting, restoring and sustainably managing terrestrial ecosystems” [109].

7.1.4 SDG 6: clean water and sanitation – water quality standards

Setting stringent water quality standards and implementing monitoring systems, as proposed by the UN Environment Program, are crucial steps toward SDG 6’s target of “ensuring access to clean water and sanitation for all” [55, 110].

7.2 Mitigation strategies

7.2.1 SDG 13: climate action – reducing the carbon footprint

The fight against plastic goes hand-in-hand with mitigating climate change. Initiatives like Kenya’s bamboo straw movement, replacing plastic with a fast-growing, naturally compostable alternative, are not just reducing plastic waste but also sequestering carbon [111]. In India, companies like Ecoware are pioneering edible seaweed-based cutlery, further slashing the carbon footprint associated with plastic production [112]. These stories exemplify SDG 13’s call to “take urgent action to combat climate change and its impacts.”

7.2.2 SDG 11: sustainable cities and communities – waste management infrastructure

Cities stand at the frontline of the plastic battle. Bogota, Colombia, has transformed its landfill into a sprawling eco-park, diverting tonnes of plastic waste from landfills [113]. Meanwhile, Amsterdam is piloting “smart bins” that monitor fill levels and optimize collection routes, boosting efficiency and reducing plastic leakage [114]. Such initiatives embody SDG 11’s goal of “making cities and human settlements inclusive, safe, resilient and sustainable.”

7.2.3 SDG 9: industry, innovation, and infrastructure – research and innovation

Innovation holds the key to breaking free from our plastic dependence. Researchers around the world are harnessing fungi that degrade plastic, offering a bioremediation solution with immense potential [115, 116, 117]. Meanwhile, start-ups in the United States are developing enzyme cocktails that can break down various types of plastic into recyclable components [118, 119, 120]. These cutting-edge solutions align with SDG 9’s focus on “promoting sustainable industrial development” and “fostering innovation.”

7.3 Individual and community actions

7.3.1 SDG 3: good health and well-being – consumer awareness

Knowledge is power in the fight against plastic. Stories like Adithya Mukerjiee, the 16-year-old activist from India who raised awareness about the dangers of plastic straws, exemplify the potential of individual action [121]. Empowering individuals with information about the health risks associated with microplastic ingestion through campaigns and educational platforms like The Story of Stuff Project’s Plastic Free July initiative encourages informed choices toward sustainable alternatives [122]. This resonates with SDG 3’s goal of “ensuring healthy lives and promoting well-being at all ages.”

7.3.2 SDG 4: quality education – educational campaigns

Educating the next generation is crucial for breaking the cycle of plastic dependence. Initiatives like the Plastic Pollution Coalition’s educational resource kits for schools or the Green Schools program in Mexico, which integrates environmental education into the curriculum, are sowing the seeds of change [123]. These efforts embody SDG 4’s focus on “ensuring inclusive and equitable quality education and promoting lifelong learning opportunities for all.”

7.3.3 SDG 17: partnerships for the goals – community engagement

Collective action holds the key to tackling the plastic crisis head-on. Local campaigns like the Great Pacific Garbage Patch Cleanup, with its dedicated volunteers tackling plastic debris in the ocean [124], or the “Adopt-a-River” initiatives in many countries, demonstrate the power of community engagement [125]. These partnerships between governments, businesses, NGOs, and communities align with SDG 17’s call to “strengthen the means of implementation and revitalize the global partnership for sustainable development.”

7.4 Everyday actions

The scale of the problem can feel overwhelming, but amidst the plastic tide, a wave of individual action is rising, driven by the spirit of the UN Sustainable Development Goals (SDGs). These everyday choices, big and small, have the power to break our dependence on plastic and build a healthier future for our planet.

7.4.1 SDG 12: responsible consumption and production – plastic-free living

Our everyday choices can create a ripple effect of change. Opting for products with minimal packaging or choosing to refill your own containers at stores like Package Free Shop in London are simple yet impactful steps [126]. Carrying a reusable water bottle and coffee mug, like those offered by companies like Hydro Flask, can dramatically reduce your reliance on single-use plastics [127, 128]. By embracing a “plastic-free living” mantra, we align with SDG 12’s call to “promote sustainable production and consumption patterns.”

7.4.2 SDG 14: life below water – cleanup initiatives

From organizing local beach cleanups like those coordinated by Surfrider Foundation to joining riverbank restoration projects, individuals can directly combat existing plastic pollution [129, 130, 131, 132]. Responsible disposal of collected plastics ensures they do not re-enter the environment, further supporting SDG 14’s goal of “conserve and sustainably use the oceans and marine resources.”

7.4.3 SDG 6: clean water and sanitation – mindful water use

Conserving water goes hand-in-hand with reducing plastic waste. Every liter saved means fewer plastic bottles are produced and consumed. Additionally, choosing sustainable personal care products and properly disposing of them helps prevent microplastics from entering our water bodies, contributing to SDG 6’s mission of “ensuring access to clean water and sanitation for all” [55, 56, 110].

The plastic pollution crisis demands urgent and collaborative action at all levels to create transformative change. While individual actions like recycling and using reusable products are invaluable, we must also harness our collective power to advocate for policy changes, invest in infrastructure, and drive widespread education and awareness. The key is scaling up pilot programs, fostering partnerships to accelerate innovation, empowering communities, and demanding stronger regulations worldwide. By embracing the collective spirit of the SDGs, we can phase out single-use plastics, develop alternative materials and technology, and usher in a new culture of sustainability. The road ahead is long, but each small act creates ripples that can swell into waves of change. If we work together, combining individual action with systemic transformation, we can stem the tide of plastic pollution and secure a healthy planet for generations to come.

8. Future challenges and research needs

The study of plastic pollution in freshwater bodies presents ongoing challenges and areas for future research. As the field evolves, researchers continue to uncover new dimensions of the issue. This section lists out the challenges and areas where research advancement is needed [16, 115, 133, 134, 135, 136, 137, 138].

8.1 Comprehensive understanding: challenge

Achieving a comprehensive understanding of the sources, pathways, and fate of plastic pollution in freshwater bodies. Research Needs: Conduct detailed studies to identify and quantify various sources of plastic pollution, including primary sources (e.g., mismanaged waste) and secondary sources (e.g., fragmentation of larger plastics).

8.2 Microplastics and nanoplastics: challenge

Understanding the full extent of the impacts of microplastics and, especially, nanoplastics on freshwater ecosystems and human health. Research Needs: Investigate the mechanisms of nanoplastic formation, their behavior in aquatic environments, and potential toxicological effects on aquatic organisms and humans.

8.3 Long-term effects: challenge

Assessing the long-term ecological and human health consequences of plastic pollution in freshwater ecosystems. Research Needs: Implement longitudinal studies to monitor the persistence of plastics in the environment, their interactions with ecosystems over time, and the potential accumulation of plastics in organisms.

8.4 Remote sensing techniques: challenge

Developing effective remote sensing techniques for monitoring and mapping plastic pollution in large and remote freshwater bodies. Research Needs: Explore the use of satellite imagery, drones, and other remote sensing technologies to assess the distribution and dynamics of plastic pollution in lakes, rivers, and other freshwater environments.

8.5 Ecological impacts: challenge

Evaluating the ecological impacts of plastic pollution on different components of freshwater ecosystems, including flora, fauna, and microbial communities. Research Needs: Conduct in-depth studies on the effects of plastic pollution on biodiversity, habitat structure, nutrient cycling, and other ecological processes in both aquatic and riparian ecosystems.

8.6 Emerging contaminants: challenge

Identifying and understanding the role of emerging contaminants associated with plastics in freshwater systems. Research Needs: Investigate the potential release of chemicals from plastics into the environment and their effects on aquatic organisms and ecosystem functioning.

8.7 Social and economic dimensions: challenge

Incorporating social and economic dimensions into plastic pollution research to address the human dimensions of the issue. Research Needs: Explore the social and economic impacts of plastic pollution on communities dependent on freshwater resources. Investigate the effectiveness of different policy measures and community engagement strategies.

8.8 Mitigation and remediation strategies: challenge

Developing effective and scalable mitigation and remediation strategies for reducing plastic pollution and removing existing plastics from freshwater bodies. Research Needs: Evaluate the performance of different cleanup technologies, such as floating barriers, skimmers, and innovative materials for plastic capture. Explore nature-based solutions and the potential for natural processes to assist in plastic degradation.

8.9 Stakeholder engagement: challenge

Enhancing stakeholder engagement and collaboration to address plastic pollution at various levels, including government, industry, and local communities. Research Needs: Investigate the social dynamics and factors influencing the adoption of sustainable practices. Evaluate the effectiveness of education and outreach programs in changing behaviors related to plastic use and disposal.

8.10 Policy effectiveness: challenge

Assessing the effectiveness of existing policies and regulations in mitigating plastic pollution in freshwater bodies. Research Needs: Evaluate the enforcement, compliance, and overall impact of current regulations. Identify gaps and opportunities for strengthening policy frameworks at local, national, and international levels.

As researchers continue to address these challenges and research needs, advancements in the understanding of plastic pollution in freshwater ecosystems will contribute to more effective management strategies and policy interventions. Additionally, interdisciplinary collaboration and the integration of diverse perspectives will be crucial in addressing the complexity of this global environmental issue.

9. Education and outreach: powerful tools in the fight against plastic pollution

The power of education and outreach offers a potent antidote. By informing individuals, communities, and organizations, we can inspire behavioral changes, promote responsible consumption, and foster a sense of environmental stewardship [103, 139, 140, 141, 142, 143, 144, 145, 146].

9.1 Engaging minds, shaping habits

At the heart of this revolution lies school curriculum integration. Weaving lessons on plastic pollution and sustainable practices into various subjects equips students with knowledge and empowers them to become responsible citizens. Field trips to recycling centres or polluted environments further solidify learning through visceral experiences.

9.2 Amplifying the message

But education alone is not enough. Public awareness campaigns utilizing media, celebrities, and influencers ignite a shared urgency. Imagine hard-hitting visuals paired with the voice of a beloved actor urging viewers to ditch single-use plastics. Such campaigns pierce through apathy and spark individual action.

9.3 Mobilizing communities

Community engagement takes education a step further. Interactive workshops empower residents with practical skills for reducing plastic use and proper waste disposal. Cleanup drives and eco-fairs transform awareness into action, fostering a sense of collective responsibility and environmental pride.

9.4 Collaboration and amplification

No one stands alone in this fight. Partnerships with NGOs and environmental organizations leverage their expertise and networks to magnify outreach efforts. Joint initiatives like awareness campaigns or community projects ensure diverse voices and resources reach a wider audience.

9.5 Online resources and action

In an age of digital ubiquity, web platforms and online courses democratize access to knowledge. Imagine an interactive website where users learn about the plastic life cycle, explore sustainable alternatives, and track their own plastic footprint. Such tools empower individuals to become agents of change, regardless of location.

9.6 Corporate responsibility and engagement

Businesses are crucial partners in this journey. Employee training programs on plastic reduction and eco-friendly practices empower workforces to become ambassadors of sustainability within their communities. Collaborations with corporations can promote sustainable packaging, reduce single-use plastics, and amplify awareness campaigns through their extensive reach.

9.7 Creativity and artistic expression

Art speaks where words falter. Artistic installations, sculptures, and performances deliver powerful messages about plastic pollution in a captivating way. Imagine a child’s drawing of a choked dolphin going viral, sparking conversations, and prompting action at dinner tables across the globe.

9.8 Citizen science and data collection

Empowering citizens in data collection fosters a sense of ownership and responsibility. Imagine a mobile app where individuals report plastic pollution hotspots, creating a real-time map of the crisis that galvanizes collective action.

9.9 Culturally tailored messages

One size does not fit all. Reaching diverse audiences requires targeted messaging. Culturally aware materials and languages ensure inclusivity and resonate with specific communities, ensuring no voice is left behind.

9.10 Continuous monitoring and improvement

Education is a dynamic process. Feedback mechanisms like surveys and focus groups enable us to assess the effectiveness of outreach programs and adapt based on emerging trends and audience needs.

9.11 Learning in action: education & outreach impact stories

Educational Initiatives Educational initiatives play a crucial role in raising awareness about plastic pollution and its impacts. For instance, Unilever partnered with The Economist Educational Foundation to create a workbook about plastics and packaging [142]. This workbook encourages young people to think about the role of plastic in our society and what more could be done to keep plastic out of the environment.

Another example is the Ocean Purpose Project created by Mathilda D’Silva. After developing three autoimmune diseases due to prolonged contact with polluted water, D’Silva sought to gain a scientific understanding of how plastic molecules work and their impact on health and the environment. Her project aims to transform water polluted by plastic microorganisms into hydrogen, thereby creating energy [145].

Outreach Programs are another effective way to combat plastic pollution. The Zero Waste Challenge, supported by UNESCO Green Citizens, is an example of an outreach program that has made a significant impact [103]. The challenge includes a range of public awareness activities, such as a monthly zero-waste newsletter, a Facebook page for promoting zero-waste events, and an online resource showcasing best practice projects [140].

GreenKayak, co-founded by Oke Carstensen, is another innovative project committed to the fight against plastic pollution. The concept behind GreenKayak is a “win-win”: having a good time by renting a kayak free of charge, taking a stroll along the river, and picking up any garbage you come across. By giving people a chance to get active and act collectively, Carstensen’s project educates people by offering them an enjoyable, sustainable tourism experience [147, 146].

The Role of Schools: Schools play a vital role in educating students about plastic pollution [140, 143, 147]. The Ocean Plastics Academy, for example, helps students develop a deep understanding of the plastics challenge [140, 146]. The Plastic Clever Schools initiative provides real-world experiences where students can apply new knowledge, practice skills, and build confidence [148, 149].

10. Conclusion

To combat plastic pollution in freshwater ecosystems comprehensively, a multifaceted strategy is necessary, addressing regulatory, mitigation, and individual aspects. The United Nations’ Sustainable Development Goals (SDGs) serve as a guiding framework for equitable solutions. Regulatory measures, crucial for tackling the issue at its source, involve enforcing production and disposal regulations, promoting sustainable alternatives, and implementing Extended Producer Responsibility (EPR) policies. Mitigation efforts focus on efficient waste management infrastructure, technological innovations, and research into alternative materials to reduce environmental impacts. Nature-based solutions and ecosystem resilience enhancement are also valuable. Individual actions play a pivotal role, with education and outreach initiatives driving behavioral change through awareness campaigns and empowerment. Aligning recommendations with specific SDGs, such as SDG 14 (Life Below Water) and SDG 12 (Responsible Consumption and Production), emphasizes the interconnectedness of environmental and societal goals. Ongoing challenges highlight the evolving nature of plastic pollution, emphasizing the need for continued research, including understanding sources, pathways, and long-term effects. Education and outreach activities emerge as powerful tools for prevention, targeting diverse audiences and utilizing creative approaches. Ultimately, collaboration, innovation, and a commitment to SDGs are essential for a sustainable and resilient future amid the challenges of plastic pollution in freshwater ecosystems.