Introduction

“Microplastic (MPs)” was coined in 2004 to address the recorded new smaller plastic particles in the range of 0.05–0.5 mm or could pass from the 500-µm sieve (Kumar et al. 2020; Magnusson et al. 2016), which are prevailing in the environment mainly due to littering and mismanaged waste. The upper size limit for microplastic was suggested as 5 mm in an international research workshop on “Occurrence, effects, and fate of microplastic marine debris” hosted by the National Oceanic and Atmospheric Administration (NOOA) in 2008. MPs have become a topic of serious concern for the environment and thus grabbed a particular focus of researchers. Accumulated data provided by further research led to an increased and sustained focus on the topic, which was not initially sustained in the first reports published in the early 1970s. “Plastics” in microplastics refers to a subclass of polymers that are a chemically long-chain arrangement of a particular chemical moiety. Because of the versatile properties of plastic, such as bio-inertness, lightweight, and moisture resistance, around one third of overall plastic resin is used solely for consumer packaging plastic (Chatterjee and Sharma 2019; Wan et al. 2019). Polymers used in plastics may be a homopolymer (composed of the same subunit throughout) or copolymers (different compositions with different sequences). Ethylene, propylene, vinyl chloride, and styrene are commonly used monomers for plastic manufacturing (Smith et al. 2018), which are present in microplastics.

Primary and secondary microplastics are the types of microplastics that are commonly found in the environment. Primary microplastics are plastic microparticulate directly released from plastic material, whereas secondary microplastics are generated via weathering or degradation of smaller fragments of plastics (Boucher and Friot 2017; Magnusson et al. 2016). Global data of mismanaged plastic waste was reported to be 99 million metric tonnes for 2015, projected to reach a tripled value of 155–265 metric tonnes by 2060 (Lebreton and Andrady 2019). Approximately 320 million tons of plastic are manufactured, and production is continuously rising, predicted to reach 33 billion tons by 2050 (Bhattacharya and Khare 2020; Chen et al. 2020). As one third of overall plastic resin is used to manufacture packaging plastic material, manufacturing at this huge level corresponds to the prevalence of microplastics in overall debris (Andrady 2011).

The aquatic ecosystem has been most intensively researched in the last few decades for microplastic contamination followed by terrestrial and atmosphere (Ng et al. 2018; Rillig et al. 2019), while data on the presence, accumulation, and significant effects in humans reported to date are significantly less (Tan et al. 2020; Yee et al. 2021). The microplastic study is vital to comprehend pollution sources, detect health risks, devise effective remediation, and protect ecosystems from plastic’s pervasive and harmful influence. Therefore, this review includes the study of microplastics in the environment, i.e., their sources, analytical detection, health concerns, and remediations.

Analysis of microplastics

Sampling and sample preparation

Microplastic content can be efficiently sampled from water, sand, soil, air, and living tissues using standard procedures, given that sampling is the most crucial step in the analysis. While developing a sample strategy, the distribution of MPs and the morphology of the site for MP sources are important factors to be considered. For soil sampling, ISO18400-102 prescribed various issues such as the types and sizes of samples required, the depth from which the samples must be taken, potential contaminants and their nature, sampling locations distribution, and other issues that must be taken into consideration (Lusher et al. 2014). Three methods have been reported for taking samples from marine sources: bulk sampling, selective sampling, and volume-reduced sampling (Hidalgo-Ruz et al. 2012). For the sampling of microplastics in air, passive atmospheric deposition and actively pumped samplers were used. Among these, actively pumped samplers are more efficient for estimating the number of microplastics inhaled by humans daily (Vianello et al. 2019). Apart from these methods, organic separation and density separation are two majorly used processes for the sampling. Sample preparation processes for MPs include drying, homogenization, sieving, sorting, dispersion of soil aggregates, density separation, removal of soil organic matter, and extraction with organic solvents. The digestion methods for sampling of marine environment comprise four methods: acid digestion (HCl, HNO3), alkaline digestion (KOH, NaOH), enzymatic digestion (protease, lipase, cellulose, etc.), and oxidizing digestion (H2O2) (Stock et al. 2019).

Identification and quantification

Microplastics can be identified using a combination of physical and chemical characterization (Shim et al. 2017). Physical characterization defines various physical characteristics of the particles. It involves various types of microscopic techniques such as dissect microscopy (Setälä et al. 2014), polarized microscopy (Lusher et al. 2020), scanning electron microscopy (Fernández-González et al. 2021), atomic force microscopy (Julienne et al. 2019), and fluorescence microscopy (Scircle and Cizdziel 2019). However, chemical characterization involves describing particles based on their chemical characteristics. Various techniques used for the identification and quantification of microplastics include energy dispersive X-ray analysis (Kumar and Sharma 2021), differential scanning calorimetry (Liu et al. 2021a, b), FT-IR (Pico et al. 2018), Raman spectroscopy (Ragusa et al. 2021), and GC–MS (Shim et al. 2017). Table 1 summarizes the techniques used by different researchers to determine the presence of microplastics in different samples.

Table 1 Techniques used for the determination of microplastic in different samples
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Remediation of microplastics from the environment

Physical methods

Physical methods to remove microplastics from wastewater include floatation, sedimentation, and filtration. Various experiments have been conducted to estimate the filtration capability of filters such as sand, membrane, and disk filters and screening (Table 2). Knoblock et al. (1994) experimented with the filtration capacity of porous membranes coupled with biological processes. This system proved to be efficient for the removal of microplastics from various industrial wastewater. An experiment was conducted to check the removal efficiencies of the disk filter, membrane bioreactor, dissolved air floating, and rapid sand filter. The results concluded that the membrane bioreactor was 99.9% efficient in removing microplastics from 6.9 to 0.005 microplastics per liter. It was also reported that membrane bioreactor, dissolved air floating, and rapid sand filtration efficiently removed microplastic irrespective of their size, even the smallest fraction of 20–100 µm (Talvitie et al. 2017).

Table 2 Various physical filtration methods and their removal efficiency
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Filtration techniques

Wastewater from several sources is transferred to various wastewater treatment plants to remove microplastic (Saur 2020). Municipal wastewater treatment plants are only efficient in removing large plastics. However, the only drawback of municipal wastewater treatment plants is their inefficiency in removing micro- and nanoplastics (Lv et al. 2019). Various wastewater treatment plant processes are divided into four steps: preliminary, primary, secondary, and tertiary treatment (Table 3). In preliminary treatment, a sedimentation tank consisting of a screen removes large and large plastics. In primary treatment, aeration and sedimentation remove light and heavy plastics by skimming and sedimentation. Secondary treatment is referred to as biological treatment, which includes an aerobic tank, anaerobic tank, anoxic tank, and a settling tank that efficiently removes microplastic below 500 µm in size. Tertiary treatment is considered an optional step that is helpful in the removal of nitrogen and phosphorus with the help of various chemicals (Wu et al. 2021).

Table 3 Various treatment procedures and their removal rate
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Chemical methods

Commonly used chemical methods for removing microplastics are coagulation and sedimentation (Fig. 1), including iron and aluminum-based coagulants. The extent of removal of microplastics is based on the type and amount of coagulant used and the retention time of coagulation. Various experiments were conducted with aluminum and iron to check the better coagulation agent, and it was concluded that aluminum showed better coagulation than iron. The microplastic removal efficiency depends upon the pH, which decreases upon increasing the pH and increases upon decreasing the pH, especially for particles below 0.5 mm in diameter. Adding polyacrylamide, an enhancing coagulation agent, showed increased removal efficiency of microplastics with a diameter below 0.5 mm. However, no significant change in removal efficiency was observed for microplastic having a diameter of 5 mm or above. It showed an increase in removal efficiency from 25.83 to 61.19% for particles (diameter < 0.5 mm), while for microplastics (2–5 mm diameter), the removal efficiency increased from 4.27 to 18.34% (Ariza-Tarazona et al. 2019).

Fig. 1
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Microplastic removal by coagulation, sedimentation, and ultrafiltration (UF) showing the effect of anionic polyacrylamide (PAM), pH, and the formation of Al-based flocs on the removal efficiency

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Biological methods

Biological methods for removing microplastics include aerobic and anaerobic digestion, lagoon, sludge treatment, and septic tank. Liu et al. (2019a) reported that virgin microplastics did not interfere with the activities of nitrite-oxidizing bacteria, ammonia-oxidizing bacteria, and phosphorus-accumulating microorganisms. It was reported that 10 mg/L of fresh Cyanothece sp. showed a 47% microplastic removal rate (Cunha et al. 2020). In another experiment, it was reported that the growth rate of Daphnia magna and the intake rate of PE increased as the exposure time and particle concentration were increased. Additionally, it was reported that Raphidocelis subcapitata exposed to PE showed more growth than those without exposure (Canniff and Hoang 2018). As such, the removal of microplastics by using a biological method is less efficient, and secondary contamination of microplastics in sedimentation or sludge can be increased (Liu et al. 2021a, b). Therefore, it was concluded that high microplastic removal efficiency by biological methods is not very optimistic.

Sources of microplastics in environments

Microplastics originates from plastic debris breakdown, synthetic fiber shedding, industrial processes, and improper waste disposal, entering water bodies and ecosystem (Fig. 2), posing environmental challenges. Mismanaged plastic waste degrades into microplastics through various methods, as shown in Fig. 3. The various plastic materials, their structure, and degraded microplastic from them are summarized in Table 4.

Fig. 2
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Contamination of the ecosystem by microplastic (Wan et al. 2019; Khalid et al. 2020; Lönnstedt and Eklöv 2016; Song et al. 2019)

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Fig. 3
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Outline of the mismanaged plastic waste degradation cascade into microplastics (Sharma and Chatterjee 2017; Smith et al. 2018)

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Table 4 The structure, use, and degradation products of the materials used to manufacture plastic materials
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Sources of microplastics in water

Carpenter and Smith et al. reported the presence of plastic pellets on the surface of the North Atlantic Ocean in 1972. They stated, “The increasing production of plastic, combined with present waste-disposal practices, will probably lead to greater concentrations on the sea surface. The only known biological effect of these particles is that they act as a surface for the growth of hydroids, diatoms and probably bacteria” (Carpenter et al. 1972). It was reported that near about 72.03 ± 19.16, particles of microplastics were present in 100 g of beach sediment (Dowarah and Devipriya 2019). The primary sources of marine pollution are fishing, domestic and industrial runoff, land plastic litter, tourism, ports, harbors, the shipping industry, and recreational activities (Fig. 4).

Fig. 4
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Sources of microplastics in the aquatic environment

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Plastic polymers are generally used to formulate personal care products such as liquid soaps, toothpaste, bubble wash, sunscreen, and hair cleaners for their specific functions such as exfoliators, hair fixatives, and volume bulking agents (Nizzetto et al. 2016). The most common type of personal care product is skincare. Polyethylene is the most often used material in skin cleansing products, accounting for around 92% of all consumption. Personal care items have been shown to contain 0.5 to 12% microplastic by weight (Magnusson et al. 2016). These plastic contents in the formulation are meant to be either rinsed off or retained on the skin’s surface. The washed-away plastic content is the potential source of microplastics in water bodies. It was reported that 256–283 microplastic particles were present upon evaluating the sand samples with FT-IR spectroscopy from Tampico beach sediments at Tamaulipas State, southern Gulf of Mexico (Flores-Ocampo and Armstrong-Altrin 2023). Another report showed that upon evaluating sand samples from Tecolutla beach sediment, the most abundant colored microplastic was black, followed by blue. These microplastics were in the form of fibers (Flores-Cortés and Armstrong-Altrin 2022).

Exfoliators used in cosmetics act as the primary source of microplastics in the water proved already (Liebezeit and Dubaish 2012; Piotrowska et al. 2020). Moreover, laundry-related activities also comprise a major part of sources of microplastic in sewage systems. Plastic fibers are rinsed out from the garments when they are washed. The proportion of acrylic and polyester fibers in sewage was comparable to that of ocean sediments. The report said a brand new fleece shirt with 100% polyester could lose 0.4% of its weight in the first four washes (Magnusson et al. 2016). Various reports showed that outdoor activities such as construction work, sports activities on school grounds, and rainwater pipelines are other sources of microplastic reaching water matrices. It was reported that polystyrene (insulation foam), polyvinyl chloride (wall insulation), and polyethylene (cable insulation) are the major plastics commonly found at construction sites. Along with these sources, various other sources have been summarized in Fig. 5.

Fig. 5
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Summarization of various possible sources of emission of microplastics in marine environments (Foley et al. 2018; Pannetier et al. 2020; Ding et al. 2018)

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Effects of microplastics on the aquatic ecosystem

Microplastics consumed by biota could pose serious problems as they may act as a vehicle for transporting persistent organic pollutants (POPs) to the organisms which are adsorbed onto microplastics (Bowmer 2010). MPs are considered bioinert for the feeders in seawater due to the lack of metabolizing enzymes in them. The toxicity of any plastic can be considered because of the following vectors: the leachate content, toxicity due to the degradation products, and MPs with adsorbed POPs which could be ingested and bioavailable to organisms. The uptake of microplastics by marine organisms created harmful effects on their biological processes. Prevalent increased mortality was found in fishes before reaching maturity due to microplastic ingestion. Microplastics are proven to be a menace for the species by several studies. The mortality rate of the fish ingested with microplastics is reported to be more than the control (Auta et al. 2017; Jovanović 2017).

Harpadon nehereus, H. translucens, and Sardinella gibbosa collected from the North Bay of Bengal were reported to contain 443 MP items in intestines as total analyzed by micro-FT-IR (Hossain et al. 2019). Shore crab (Carcinus maenus) was reported for the uptake of microplastics by inspiration via gills along with ingestion which was found to be retained in the body for 21 days (inspirated) and 14 days (ingested). Hence, ventilation was concluded for the uptake of MPs in it (Watts et al. 2014). Uptake of MPs in gonads, digestive, and water vascular systems in sea urchins has been reported along with an increase in reactive oxygen and nitrogen species and increased immune cells as effects them (Murano et al. 2020). A concentration-dependent rise in bioaccumulation and reactive oxygen species during exposure to polystyrene microplastics was reported in shrimp (Suman et al. 2020). DNA damage and increased oxidative stress due to increased production of reactive oxygen species and altered antioxidant parameters after the microplastic ingestion are already reported (Hamed et al. 2020).

Sources of microplastics in soil

Various sources of microplastics reaching soil are plastic mulching, sewage sludge, and contaminated water resources. Plastic mulching is the practice of covering the soil with a polyethylene sheet to increase plant growth by maintaining high moisture content and temperature, reducing seed time and harvest time, and limiting weed growth (Espi et al. 2006). Plastic mulches are used due to their ability to transmit or reflect the selective wavelength of light. Approximately 20 million hectares of farmland use plastic mulching (Steinmetz et al. 2016). Polyethylene (low-density polyethylene, high-density polyethylene, linear low-density polyethylene) has become a significant foundation for manufacturing highly customizable mulch films with appropriate flexibility and ease of handling, life, and lack of toxicity and odor (Kara and Atar 2013). Different microplastic shapes negatively impacted soil aggregation, whereas root and shoot mass increased regardless of polymer type. Fibers, fragments, films, and foams were found to reduce soil aggregation by 29%, 27%, and 20%, respectively. Propylene was the most active in reducing microbial activity in soil (Lozano et al. 2021). Water employed in use for the irrigation of crops acts as a potential source of MPs in soil. The vegetables grown in greenhouses require heavy irrigation, proper fertilizers, and intensive cropping. Using wastewater due to its easy accessibility may lead to MPs in soil. Also, the runoff from streets directly from the fields provides soil with a heavy amount of microplastics (Zhang et al. 2020a, b). The water used in irrigation could contain microplastic contaminants, especially if it is street runoff or the effluent of textile, polymeric, or other industries. Water, due to its easy accessibility, contributes to soil contamination primarily. Factors like abundant availability of wastewater, heavy irrigation, and intense cropping practices for greenhouse vegetables or crops also affect the soil’s microplastic content (Zhang et al. 2020a, b). Surface and landfill deposits contribute to the dispersion of microplastic particles into the atmosphere, which could be transported further to fields by atmospheric deposition. Rainfall potentially influences the fallout flux of atmospheric MP pollution.

Effects of agricultural microplastics on plant health

Macahdo et al. reported in their study that microplastic fibers in concentrations 0.05 to 0.40% affected soil physical properties much more than microplastic beads in concentrations 0.25 to 2.00% (de Souza Machado et al. 2018). The presence of microplastics in soil provides an altered structure to it by lowering the bulk density of soil, which results in decreased resistance of soil to the root and hence better aeration and root growth; on the other hand, it provides better conditions for the water evaporation from the soil, i.e., the soil would be dry. Yong Wan et al., in their study, reported that water evaporation of soil was increased due to microplastic particles due to increased water conductivity of soil, and the evaporation was dependent on the size and concentration of MPs. MPs with a diameter of 2 mm had a more pronounced effect than MPs with a diameter of 10 mm (Wan et al. 2019). Direct toxicity of microplastics could be mediated by blockage of seed pores, limiting uptake of nutrients and water through roots, and accumulation in roots, leaves, and other parts of the plant (Khalid et al. 2020). Previously, there was no evidence of microplastic uptake in plants; however, Lianzhen Li et al. recently reported on the uptake of microplastic beads in plants. Fluorescence methods were used to trace the absorption of polystyrene microplastic beads with diameters of 0.2 µm and 1.0 µm by the plant. The beads were also scattered about in the leaves (Li et al. 2019). Nanoplastics can be uptake as well as accumulate in plants. The surface charge on nanoplastics influences the amount of microplastic uptake and accumulation. Positively charged nanoplastics were reported to induce the accumulation of a higher amount of reactive oxygen species and inhibited plant growth and seedling development compared to negatively charged nanoplastics (Sun et al. 2019).

Sources of microplastics in air

Air pollution with microplastic as a pollutant is becoming a serious problem steadily. With the increasing production and usage of plastic items, the microplastics emitted from various sources enter the atmosphere, polluting it to a concentration above a significant level. The microplastics (mainly fibers) remain suspended in the air and can be transported to different places by the wind. These suspended microplastics could be inhaled directly by humans. The changes in respiratory and ventilator functions by the microplastic contaminants have been highlighted by Zuskin and Pimental (Mbachu et al. 2020). Various anthropogenic activities leading to MPs in the air are categorized into three main classes: industrial, agricultural, and domestic. The synthetic textile industry is considered the most contributing factor to MPs in the air (Chen et al. 2020; Mbachu et al. 2020). Production of synthetic textiles is increasing continuously due to their properties: strong and durable, resist wrinkles, resist chemicals, do not shrink on wash, low moisture absorbance, and resistant to fungal growth (Deopura and Padaki 2015). Polyethylene being very light is used in a wide range of products for different purposes. Atmospheric fallout comprises (as found to be) of polypropylene, polystyrene, polyethylene, and polyethylene tetraphthalate as dominant polymers in microplastics. Microplastics are released during abrasion, wear, or other activities like cleaning and drying (Napper and Thompson 2016). Catherine Stone et al. has thoroughly analyzed and concluded that synthetic textile has more fiber emission in usage but not in manufacturing. In comparison, woollen textiles produce more fiber emissions while manufacturing (Stone et al. 2020).

Kai Liu et al. analyzed the suspended atmospheric microplastic particles from the air samples from Shanghai using an active suspended particulate sampler. They estimated that around 270 kg of SAMS was transported via air from Shanghai. Textiles were concluded to be the primary source of MPs in the air (Liu et al. 2019b). Agricultural activities involving the incorporation of sewage sludge in soil for the renovation of organic content, plastic mulching for moisture retention and soil temperature maintenance, biocompost, and use of contaminated water for irrigation all act as potential microplastic contaminants to the soil. The microplastics from all these activities quickly spread and are suspended in the air, contaminating it. Domestic activities like unmanaged dustbins and landfill sites, plastic littering, and the use of plastic-made household items potentially cause the emission of microplastics into the air. Christian Ebere Enyoh et al. has reviewed the research on dust samples collected from different locations (mainly from Asia, Europe, and the West Pacific Ocean) analyzed for microplastics content (Enyoh et al. 2019). Transport, dispersion, and deposition are reported for moving microparticles in the air from one place to another.

Effects of suspended air microplastics

Microplastics can be inhaled easily into human lungs, but it depends upon the size of MP. Inhalable in the true sense refers to the ability to enter via mouth or nose and get deposited in upper respiratory airways. In contrast, those which could reach and deposit to the deeper lungs are generally referred to as respirable (Gasperi et al. 2018). Suspended air microplastics (SAMPs) adsorbed with microorganisms could source infections in the host organisms. Scarce research work has been done on investigating the effects of MPs on human tissues. In the first report of this type, Kerestin E. Goodman et al. investigated the toxicological effects of MPs on cultured human alveolar cells. They reported the changes in the cell proliferative and morphological changes as effects. An uptake of 1 µm microplastic, a dramatic decrease in metabolic activity, proliferative rate, and little cytotoxicity were the effects concluded, which proposes the consequence of microplastics to human lungs (Goodman et al. 2021). Alveoli, alveolar ducts, and terminal bronchioles are the sites in the lungs where fibers can accumulate and hence can cause chronic inflammation, granulomas, or fibrosis (Beckett 2000). Oxidative stress caused by MPs can lead to chronic inflammation and pave the way to lung diseases. The improper disposal of the items such as vinyl gloves, plastic ventilator components, visors, facemasks, gowns, and bags used in the COVID-19 pandemic could release many MPs into the environment (Amato-Lourenço et al. 2020; Aragaw 2020).

Sources of microplastics in humans

Microplastics can enter the human body through interrelated systems and activities. The air we breathe, the food we eat, the liquids we drink, and the human environment are the core broad categories that encompass all activities that expose humans to microplastics. Microplastics in marine water bodies are directly proportional to the microplastic content of seafood and other sea animals. Ana I. + Catarino and colleagues investigated the microplastic concentration of mussels. They reported the same concerning human microplastic ingestion through dust during meal consumption. Visual assessment of microplastic fibers using Nile red staining and FT-IR techniques yielded 48% and 50% accuracy, respectively (Catarino et al. 2018). It was reported that shellfish users might swallow 1358 microplastic particles every year. However, the extent is determined by the variety and quantity of shellfish consumed and the level of seafood removal by an individual’s intestines (Daniel et al. 2021). It was found that salt derived from seawater or lake water also contains microplastics and can be backed by the known relation between the microplastic concentration in seawater and marine creatures. The content of microplastics in source water serves as a source of microplastics for salt production. A report showed that 21 Spanish table salt samples contained PET as the major polymer, near about 50–280 MPs/kg of sample (Iñiguez et al. 2017). M. Sivagami et al. studied different salt samples from Indian supermarkets, confirming the presence of microplastic content and evaluating the toxicity profile of MP content. The average abundance was 700 MPs/kg, with particle sizes ranging from 3.8 µM to 5.8 Mm.

Effects of microplastics on human health

Several reports provide evidence of the ingestion of microplastic in humans through diet. Based on the American diet, the annual human consumption of microplastics has been estimated to be 74,000 to 121,000 microparticles, while the persons using bottled waters to stay hydrated were estimated to consume an additional 90,000 MPs annually. The enhanced apoptosis rate of HEK-293 cells treated with MPs was used to prove MP’s lethality (Sivagami et al. 2021). A variety of consumable items, including fish (Daniel et al. 2021), crabs (Watts et al. 2014), mussels (Catarino et al. 2018), table salt (Iñiguez et al. 2017; Lee et al. 2021), energy drinks and soft drinks (Shruti et al. 2020), white wine (Prata et al. 2020), mineral water bottles (Lee et al. 2021), milk products (Andrey et al. 2021), and tea bags have been reported widely as being the source of microplastics for humans. Microplastics may alter stored energy utilization and impair the body’s defensive action against pathogens after ingestion and accumulation in the human body. The four hypothesized mechanisms by which microplastics may enter the human body through the respiratory system and gastrointestinal tract are passive diffusion, upper airways, lower airways, and endocytosis by M-cells (Ragusa et al. 2021). Lixin Wang et al. investigated and found the enhanced toxicity of polystyrene microplastics in the form of increased apoptosis and membrane alterations due to the degradation of MPs in the presence of simulated gastric fluid (Wang et al. 2021). The uptake of microplastics in mammalian testicles has been investigated and reported. Since spermatogenesis is such a delicate process, the presence of microplastics and chemical contaminants on it has a significant impact (decreased sperm quality) (D’Angelo and Meccariello 2021). Uptake of polystyrene nanoplastics in Caco-2 cells enhances the mitochondrial activity and hindered ABC transporter and toxicant effluent pump, resulting in increased arsenic toxicity (Fig. 6) (Wu et al. 2019).

Fig. 6
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Routes of entry and effect of microplastic on the human body

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Conclusion

Microplastics are defined as synthetic solid particles or polymeric matrices with sizes ranging from 0.05 to 5 mm, belong either to the primary or secondary origin, and are insoluble in water. Polymer science, one of the most revolutionary fields, has come up with indispensable compounds such as PVC, PE, and many polymers with numerous applications in everyday life. Despite this, rising production, consumption, and incorrect disposal contribute to rising global environmental concerns. Microplastics are being continuously investigated to explore the sources, safety, sophisticated techniques or analysis, and potential hazards concerning human and environmental health, as both are interconnected. The number of reports on the presence of MPs in human dietary food items is continuously increasing. Emerging evidences are available for the presence of MPs in human-consumed seafood, beverages, and other food items. Human ingestion and inhalation of MPs and their substantial risks to human health have already been suggested.

In this review, an efficient approach has been executed to compile the recent research and reported knowledge on the issue. The sources of MPs in context to marine, agriculture, atmosphere, and humans, the potential hazards to different ecosystems and humans are adequately covered. Emerging sources of microplastics like textiles and cosmetics are discussed. Advanced techniques detection and quantification of microplastics, including spectroscopic methods, offer more comprehensive insight. The effects of MPs on humans and their mechanisms have been briefed. In addition, the sampling, processing, and analytical methods employed so far have been described. Physical, chemical, and biological remediation approaches used for removing microplastics from water bodies have been discussed for their appropriate future implementation. The absence of guidelines and specifications for controlling MPs in the environment makes it a trending field for the researcher and the regulatory agencies for future research.