Received: 21 April 2025 Revised: 29 April 2025 DOI: https://doi.
org/10.
31102/eam.
Accepted: 2 June 2025
Available online: 3 June 2025
REVIEW ARTICLE
Interaction of microplastics and heavy metals on aquatic organisms : A review Adinda Kurnia Putri1,*.
Yenni Arista Cipta Ekalaturrahmah2.
Ahmad Ahmad2.
Moh Shoheh2 1Department of Aquatic Resources.
Jendral Soedirman University.
Banyumas Central Java, 53122.
Indonesia Centre for Environmental and Agriculture Management.
Universitas Islam Madura Correspondence Adinda Kurnia Putri.
Department of Aquatic Resources.
Jendral Soedirman University.
Banyumas Central Java, 53122.
Indonesia.
Email: adinda.
kurnia@unsoed.
Abstract Microplastics, which originate from a variety of sources and are widespread in aquatic ecosystems, have a significant capacity to adsorb heavy metals through a variety of physicochemical mechanisms, including electrostatic interactions, complex formation, ion exchange, and surface precipitation.
A systematic review was used in this study of 50 published articles on the interactions of microplastics and heavy metals on aquatic organisms.
The characteristics of microplastics .
ize, shape, type of polyme.
and environmental conditions .
H, salinity, dissolved organic matte.
greatly influence the adsorption efficiency and behavior of microplastics in the aquatic environment.
Once inside the organism through direct consumption, gills, cuticle penetration, or cellular translocation, microplastics can release adsorbed heavy metals, creating effects that increase the bioavailability and toxicity of the metal.
Biological responses that occur include oxidative stress.
DNA damage, disruption of the antioxidant defense system, histopathological changes in tissues and organs, growth and reproductive disorders, and behavioral At the population and ecosystem level, microplastic-heavy metal interactions can lead to shifts in community composition, disruption of food webs, changes in biogeochemical cycles, and degradation of ecosystem services.
KEYWORDS
heavy metals.
INTRODUCTION
Pollution of microplastics and other pollutants, particularly heavy metals, has been a major threat to global aquatic ecosystems in recent decades (Haque.
Xiang et al.
, 2.
Microplastics, defined as plastic particles less than 5 mm in size, are found in almost all aquatic environments ranging from deep ocean to freshwater, and even drinking water (Hale et al.
, 2020.
Horton et al.
, 2.
The combination of microplastics and heavy metals creates a Environ Agri Manage.
potentially synergistic pollution complex, where microplastics can act as vectors that transport heavy metals and increase their bioavailability and toxicity to aquatic organisms (Adeleye et al.
, 2024.
Cao et , 2021.
Kajal & Thakur, 2.
Microplastic pollution varies significantly across different aquatic In open oceans, levels range between 002 and 62.
50 item/mA (Mutuku et al.
, 2.
while coastal regions exhibit concentrations from 001 to 140 particles/mA (Albaseer et al.
, 2.
https://journal.
id/index.
php/eam A 2025 EAM All right reserved Freshwater lakes show even greater variability, with microplastic accumulation reaching up to 540 MP/kg (Pierdomenico et al.
, 2.
Similarly, in water samples, microplastic abundance has been recorded at 0.
5 to 0.
9 particles per liter (Garfansa et , 2.
Heavy metal contamination is also prevalent, with chromium (C.
levels in sediment and water measuring up to 55 mg/kg and 86.
mg/L, respectively (Rakib et al.
, 2.
Additionally, cadmium (C.
concentrations have been reported between 0.
019 and 0.
025 mg/L (Elhussien & Adwok, 2.
46 to 4.
40 g/L (Sabbir et al.
, 2.
This phenomenon raises serious concerns for the integrity of aquatic ecosystems, biodiversity, and may ultimately impact human health through the food chain, making understanding of these complex interactions a priority in contemporary environmental research.
Previous research has resulted in significant advances in understanding the dynamics of interactions between microplastics and heavy metals and their impact on aquatic organisms.
Various studies have characterized the adsorption capacity of microplastics against different types of heavy metals such as cadmium, lead, mercury, and copper, taking into account factors such as particle size, polymer type, and environmental conditions (Cao et al.
, 2021.
Kinigopoulou et al.
, 2022.
Kutralam-Muniasamy et al.
, 2021.
Naqash et al.
Tang et al.
, 2022.
Zhou et al.
, 2.
The interaction between microplastics and heavy metals poses significant environmental risks, especially since they can lead to increased bioaccumulation in Research by Han et al.
shows that polyethylene (PE) has a higher heavy metal adsorption capacity than polypropylene (PP) due to its more porous surface structure.
The adsorption process for both types of microplastics follows a quasi-secondary kinetic model, but PE consistently exhibits a higher rate of adsorption (S.
Wang et al.
Toxicology research has demonstrated the effects of microplastics and heavy metals at various levels of biological organization, from cellular and molecular responses to behavioral and reproductive PUTRI ET AL changes in diverse aquatic organisms (Das, 2023.
Vimalkumar et al.
, 2022.
Vo & Pham, 2021.
Wu et , 2.
In addition, bioaccumulation and microplastic and heavy metal transfer pathways through the aquatic food chain, suggesting a greater potential risk to high-level predators, including humans (Beuianu et al.
, 2024.
Dang et al.
, 2021.
Marcharla et al.
, 2024.
Sawangproh & Paejaroen.
Most studies were short-term .
ours to day.
, whereas environmental exposure was chronic.
of data on the characteristics of microplastics in the environment, interactions of microplastics and heavy metals.
Adsorption-Desorption mechanisms, entry pathways, biological responses, and LongTerm Ecological Implications.
Despite significant research progress, a number of constraints and knowledge gaps still hinder a comprehensive understanding of the interactions of microplastics and heavy metals on aquatic The transfer mechanisms and bioavailability of heavy metals adsorbed to microplastics in biological systems are still not fully understood, especially how the physiological conditions of organisms can affect desorption and absorption (Kumar et al.
, 2022.
Menyndez-Pedriza & Jaumot, 2.
The limitations of standard methodologies for the characterization and quantification of microplastics in complex biological samples make it difficult to compare between studies and establish accurate doseresponse relationships .
e Ruijter et al.
, 2.
addition, the majority of research focused on shortterm exposure and used unrealistic concentrations of pollutants in an environmental context, while the effects of chronic exposure on relevant environmental concentrations as well as transgenerational impacts are still very limited (Hamilton et al.
, 2.
The lack of understanding of the synergistic, antagonistic or additive effects of mixtures of different types of microplastics and heavy metals is also a challenge in accurately predicting ecological risks.
Although a lot of research has been done, the gap in understanding PUTRI ET AL remains for three main reasons: .
The mechanism of heavy metal-microplastic transfer is highly dependent on unstable environmental conditions, making it difficult to generalize the results of laboratory studies.
The bioavailability of heavy metals adsorbed by microplastics has not been fully quantified in the food chain, especially in high-level and .
Standard methods for measuring these interactions are still evolving, causing inconsistencies in data between studies.
This review article aims to integrate and synthesize the current knowledge on the interactions of microplastics and heavy metals and their impact on aquatic organisms, with a particular focus on the adsorption-desorption mechanisms, pathways into organisms, biological responses at various levels of organization, and long-term ecological implications.
The significance of this review lies in its ability to identify critical knowledge gaps and provide a comprehensive conceptual framework for understanding the ecological risks of these mixed Furthermore, this synthesis of knowledge will serve as a solid scientific basis for the development of effective environmental management and policy strategies in addressing the increasingly complex problem of mixed pollution, as well as contributing to sustainable conservation and preservation efforts of aquatic ecosystems.
METHODS
The literature review was carried out by searching for related scientific publications using the Scopus database .
The search was conducted using key terms such as "microplastics", "interactions", "aquatics".
AumetalAy, "organisms", to gather the necessary information.
Five keywords used in the livelihood process, resulting in 2748 articles.
The specific criteria for this review article is that it must be published in a Scopus indexed journal.
Furthermore, articles are selected based on the relevance of the title, abstract and articles with research categories.
Relevant data are systematically extracted and analyzed to identify key findings related to the topic of this review.
Finally the 50 most relevant articles were selected and used in this study.
CHARACTERISTICS OF
MICROPLASTICS IN THE AQUATIC
ENVIRONMENT
Microplastics are defined as plastic particles less than 5 mm in size in all dimensions, although the lower limit of size varies in the scientific literature (Shamskhany et al.
, 2.
Based on their origin, microplastics are classified into two main categories: primary and secondary microplastics (Song et al.
, 2.
The spatial distribution of primary and secondary microplastics shows different patterns in aquatic environments, with primary microplastics .
icrobeads, nurdles, and textile fiber.
tending to be dominant in open waters .
-75% of total microplastic.
due to the ability to transport over long distances via ocean currents and wind-driven transport (Alfaro-Nyyez et al.
, 2021.
Sterl et al.
, 2.
In contrast, secondary microplastics resulting from larger plastic fragmentation are more common in coastal and nearshore areas .
-85% within a 1 km radius of shor.
due to higher fragmentation intensity due to UV exposure, mechanical abrasion from wave action, and proximity to terrestrial sources of plastic debris (Kumar et al.
, 2025.
Pal et al.
, 2.
Primary microplastics are particles that are deliberately produced in micro sizes for specific applications, such as microbeads in personal care products, plastic resin pellets .
as industrial raw materials, and synthetic microfibers from textiles (Hafeez et al.
, 2.
Secondary microplastics are formed through the fragmentation of larger plastic products due to physical, chemical, and biological degradation processes in the environment, such as mechanical abrasion, photodegradation, and biodegradation (Andrady & Koongolla, 2022.
Mishra et al.
, 2.
Based on their morphology, microplastics are classified into several main forms: fragments .
rregular piece.
, fibers/filaments .
longated structure.
, films .
hin sheet.
, foam .
orous structure.
, pellets .
ylindrical or disc-shaped granule.
, and beads .
pherical particle.
(Hafeez et , 2.
The composition of microplastic polymers is very diverse, with the most common polymers found in aquatic environments being polyethylene (PE), polypropylene (PP), polystyrene (PS), polyethylene terephthalate (PET), and polyvinyl chloride (PVC), reflecting global patterns of plastic production and use (Fan et al.
, 2021.
Fernyndez-Gonzylez et al.
, 2.
The source of microplastics to the aquatic environment is very diverse and widespread (Wang et al.
, 2.
Land-based sources include poorly managed plastic waste, urban runoff containing particles from the degradation of plastic and fiber products from synthetic textile washing, wastewater treatment plant effluent containing microbeads from personal care products and microfibers from laundry, and agricultural activities that use plastic mulch films and fertilizers containing microplastics (Onyeabor, 2.
Marine-based sources include lost or discarded fishing equipment, peeling ship paint, and waste from ship operations and offshore installations (Onyeabor, 2024.
Watson et al.
, 2.
Atmospheric transport has also been identified as an important pathway for the long-distance movement of microplastics, with microplastic particles detected in atmospheric dust and dust deposits.
PUTRI ET AL
the surface of the plastic, increases the overall density and causes previously floating particles to sink (Gaylarde et al.
, 2023.
Miao et al.
, 2.
The degradation of microplastics in the aquatic environment occurs through a combination of physical, chemical, and biological processes (Corcoran, 2022.
Debroy et al.
, 2.
Photodegradation through UV radiation becomes the dominant degradation mechanism in the upper pelagic zone, resulting in the formation of oxygen functional groups on plastic surfaces and increased material brittleness (Pinto et al.
, 2024.
Wang et , 2.
Chemical hydrolysis plays a greater role in sediments, although the rate is much slower (Dimassi et al.
, 2.
Mechanical degradation through abrasion by wave action, friction with sediments, and biological activities such as grinding in the digestive tract of biota contribute to further fragmentation (Issac & Kandasubramanian, 2021.
Kumar et al.
, 2.
Biodegradation is very limited to most conventional synthetic polymers, although some specialized microorganisms have been identified to degrade certain polymers (Mukherjee et al.
, 2.
FACTORS AFFECTING THE FATE AND
BEHAVIOR OF MICROPLASTICS IN THE
ENVIRONMENT
Photodegradation through UV radiation becomes the dominant degradation mechanism in the upper pelagic zone, resulting in the formation of oxygen functional groups on plastic surfaces and increased material brittleness Density is the main factor that influences the floating or submerged behavior of microplastics in the water column (Almeida et al.
, 2023.
Feng et al.
Polymers with a lower density than water (PE: 0.
97 g/cmA.
PP: 0.
91 g/cmA) tend to float on the surface, while polymers with higher densities (PVC: 1.
41 g/cmA.
PET: 1.
g/cmA.
PS: 1.
09 g/cmA) tend to sink (S.
Liu et , 2022.
Meneses Quelal et al.
, 2.
However, this behavior can change significantly over time due to biofilm colonization .
, in which microorganisms and organic matter accumulate on Microplastic transport is affected by hydrodynamics such as current circulation, wave action, and turbulence (Kumar et al.
, 2.
rivers, microplastic concentrations show variation based on water discharge, with increases during flood events when sediment is resuspended (Xiaorong Lu et al.
, 2.
In the marine environment, thermohaline circulation and surface currents affect global distribution, causing accumulation in marine gyres (Lima et al.
, 2.
Wind forcing and internal waves can affect the vertical distribution in the water column (Fourniotis.
PUTRI ET AL In the deep sea, turbidity currents and solid water cascades facilitate the transport of microplastics to deep-sea sediments (Pierdomenico et al.
, 2.
Microplastic transport is affected by hydrodynamics such as current circulation, wave action, and turbulence The interaction between microplastics and biotic factors also affects fate and behavior.
Absorption by organisms can alter spatial distribution, while joint excretion of fecal material can accelerate vertical export to sediment through a "rain" of rapidly sinking fecal particles (Qian et al.
Excavation and bioturbation activity by benthic organisms can remobilize microplastics in sediments or bury them deeper, affecting their longterm persistence and bioavailability (Venyncio et al.
Absorption by organisms can alter spatial
distribution, while joint excretion of fecal
material can accelerate vertical export to sediment through a "rain" of rapidly sinking fecal particles ADSORPTION-DESORPTION
MECHANISM
1 Mechanism of Adsorption of Heavy Metals in Microplastics Figure.
1 Show the process of adsorption of heavy metals in microplastics involves several complex physicochemical mechanisms (Cao et al.
First, electrostatic interactions occur when the surface charge of microplastics .
sually negative due to the degradation process that results in carboxyl group.
attracts positively charged metal ions such as CdAA.
PbAA, and CuAA (Patra, 2.
Second, the formation of complexes .
occurs between metal ions and oxygen functional groups on the surface of oxidized microplastics, such as carbonyl, hydroxyl, and carboxyl groups (He et al.
, 2.
Third, ion exchange can occur where metal cations replace hydrogen ions from functional groups on the surface of microplastics.
Fourth, surface precipitation occurs when the concentration of metal ions is high, causing the deposition of metal compounds on the surface of microplastics (Xiao Lu et al.
, 2.
Figure 1.
Heavy metal and microplastic adsorption mechanism.
Source : (Prabhu et al.
, 2.
The adsorption efficiency is greatly influenced by the environmental conditions of the waters (Miranda et al.
, 2.
pH plays an important role as it affects the surface charge of microplastics and metal speciation.
generally adsorption increases at higher pH for most cationic metals due to the deprotonation of functional groups (Tang et al.
Salinity affects adsorption through the effect of ion competition, where cations such as NaA.
KA.
Ca, and MgAA in seawater compete with heavy metal ions for binding sites on microplastics.
Dissolved organic matter (DOM) can form a layer on the surface of microplastics, creating additional binding sites for metals or competing with microplastics for metal bonding (Zhu et al.
, 2.
2 Mechanism of Desorption and Transfer to Organisms The desorption of heavy metals from microplastics in aquatic organisms is affected by specific physiological conditions (H.
Pan et al.
In the digestive tract of organisms, significant changes in pH .
sually more acidic than the external environmen.
can increase the solubility of metalmicroplastic complexes (Zink et al.
, 2.
Digestive enzymes and bile acids can degrade biofilms on microplastic surfaces and release bound metals (I.
Pan et al.
, 2.
The gut microbiota environment can also change the redox shape of metals, affecting their mobility (Bist & Choudhary.
The variation in species response to heavy metal desorption from microplastics is significant.
In fish, acidic stomach conditions .
H 1.
5Ae3.
and short retention times accelerate the release of metals such as Cd and Pb, while in filter-feeder invertebrates .
, shellfis.
, a neutral digestive environment .
H 6.
5Ae8.
and prolonged particle retention increase chronic metal accumulation (Jeyasanta et al.
, 2024.
Wu et al.
, 2.
These differences suggest that the bioavailability of metals depends not only on the characteristics of the microplastics, but also on the physiological adaptations of the target organism.
Once the metal is desorpated, several absorption pathways can occur: .
direct absorption through the intestinal PUTRI ET AL epithelium, where the metal enters the bloodstream and is distributed to various organs, .
absorption by gill epithelial cells when very small microplastics reach the gills, and .
penetration through the skin or external membranes for smaller organisms (Hu et , 2.
Very small microplastics .
can cross the cellular barrier through endocytosis, potentially carrying metals directly into cells.
In the digestive tract of organisms, significant changes in pH .
sually more acidic than the external environmen.
can increase the solubility of metalmicroplastic complexes ENTRY PATH Direct consumption is the most dominant entry route for microplastics that adsorb heavy metals into aquatic organisms (Fig .
Filter feeder organisms such as shellfish, oysters, and zooplankton actively filter water and ingest microplastic particles that look like food (Fabra et al.
, 2.
Visual predators such as fish and waterfowl often mistakenly identify microplastics as prey due to their similarities in size, color, and shape to natural organisms (Benson et al.
Indirect consumption occurs when organisms feed on prey that has accumulated microplastics, creating trophic transfer pathways (Provencher et al.
, 2.
Research shows that aquatic organisms of various sizes and trophic levels, from zooplankton to predatory fish, consume microplastics to varying rates based on the type of food and feeding strategy (Uy & Johnson, 2.
Visual predators such as fish and waterfowl often mistakenly identify microplastics as prey due to their similarities in size, color, and shape to natural organisms PUTRI ET AL Figure 2.
The transfer of microplastics (MP) between trophic levels in animals suggests that organisms at higher trophic levels experience greater MP accumulation as a result of consuming contaminated prey.
The black dot describes the location of MP accumulation in the organism's Gills are the second important entry route, especially for very small microplastics and nanoplastics .
-1000 n.
(Guerrera et al.
, 2.
These small particles can be trapped in the gill filaments during the process of respiration and filtration (Alsafy et al.
, 2.
Microplastic absorption by gills occurs through a filtration mechanism and direct contact with gill filaments and secondary lamellae, where microplastic particles measuring 1-100 m can be trapped in the mucus layer and then integrate with the respiratory epithelium through the process of endocytosis or physical penetration (Liu et al.
, 2024.
Zheng & Wang, 2.
The accumulation of microplastics in the gill structure causes morphological disorders in the form of epithelial hyperplasia, fusion of secondary lamellae, and increased mucus production in a defensive response, which significantly reduces the effective surface area for gas exchange and can reduce oxygen uptake efficiency by 15-30% (Hamed et al.
, 2021.
Kama et , 2.
Further physiological impacts include chronic inflammation characterized by infiltration of inflammatory cells, increased activity of antioxidant enzymes such as catalase and superoxide dismutase in response to oxidative stress, as well as histopathological changes in the form of desquamation and necrosis of the gill epithelium that can progress to respiratory distress and decreased aerobic capacity of the organism (Sayed et al.
, 2.
In addition, microplastics accumulated in gills can act as vectors for the transfer of adsorbed heavy metals into the circulatory system through rich vascularization of gill tissue, thereby increasing the bioavailability of contaminants and magnifying the risk of systemic toxicity (Ghosh et al.
, 2025.
Liu et al.
, 2.
This condition causes prolonged contact between metal-containing microplastics and highly vascularized tissues, facilitating metal desorption and direct absorption into the bloodstream (Cameron et al.
, 2.
Absorption through gills is particularly relevant for fish, crustaceans, and shellfish.
Various studies have shown that heavy metals desorpted from microplastics in the gill area can enter the tissues without passing through the digestive tract, causing significant accumulation in these respiratory organs BIOLOGICAL RESPONSE Simultaneous exposure to microplastics and heavy metals triggers complex oxidative stress responses in the cells of aquatic organisms (Chen et , 2.
The increased production of reactive oxygen species (ROS) occurs through a dual mechanism: microplastics can physically disrupt cellular membranes and organelles such as mitochondria, while heavy metals such as Cu.
Cd, and Hg participate in the Fenton reaction that produces highly reactive hydroxyl radicals (Waqas et al.
, 2.
Studies on zebrafish showed that exposure to a combination of polyethylene (PE) and cadmium (C.
microplastics resulted in up to 2.
5fold increase in malondialdehyde (MDA) levels and decreased superoxide dismutase (SOD) activity compared to exposure to each pollutant separately.
PUTRI ET AL demonstrating a synergistic effect on cellular redox status (Wazne et al.
, 2.
Disruption of the antioxidant defense system often occurs when cells are exposed to a combination of microplastics and heavy metals (Chen et al.
, 2.
The activity of detoxifying enzymes such as catalase, glutathione peroxidase, and glutathione-S-transferase is significantly modulated, generally showing decreased capacity at chronic exposure (Abdelfattah et al.
, 2.
Changes in antioxidant gene expression and detoxification occur through pathways such as nuclear factor erythroid 2-related factor 2 (Nrf.
and aryl hydrocarbon receptor (AhR) pathways (Zhao et , 2.
Metallothionine, a cysteine-rich metalbinding protein, often undergoes up-regulation in response to metal exposure, but the presence of microplastics can interfere with this protective function through interaction with metal-binding proteins or interfere with cellular signals that regulate their expression (Menone & Pyrez, 2023.
Rai et al.
, 2.
DNA damage increases significantly in organisms exposed to a combination of microplastics and heavy metals (Turna Demir et al.
The mechanism of damage includes the oxidation of DNA bases by ROS, the formation of DNA adduct by reactive metabolites, and disruption of DNA repair mechanisms (Juan et al.
, 2.
Studies on the sea mussels Mytilus galloprovincialis showed that simultaneous exposure to polystyrene (PS) and lead (P.
microplastics increased the frequency of micronuclei in hemocytes by up to 3 times compared to controls, indicating severe genotoxic damage (Pappa et al.
, 2.
Epigenetic disorders are also observed, including changes in DNA methylation, histone modification, and microRNA expression, which can have transgenerational implications in aquatic organism populations (Z.
Liu et al.
, 2.
DNA damage increases significantly in organisms exposed to a combination of microplastics and heavy metals LONG-TERM ECOLOGICAL
IMPLICATIONS
Long-term exposure to a combination of microplastics and heavy metals can fundamentally alter the structure and population dynamics of aquatic organisms (Turna Demir et al.
, 2.
The selective pressures posed by these combined toxicities tend to favor individuals with higher pollutant tolerances, potentially reducing the genetic diversity of the population (Cao et al.
, 2.
Research on the crab Carcinus maenas showed that populations chronically exposed to a combination of experienced a 35% decrease in genetic variability after four generations (Chen et al.
, 2.
This reduction in genetic diversity weakens the adaptive capacity of populations, making them more vulnerable to additional environmental pressures such as climate change, pathogens, or the introduction of invasive species.
The differential sensitivity of different species to this combination of pollutants can lead to significant shifts in the composition of aquatic communities (Adeleye et al.
, 2.
More sensitive species such as amphipods and larvae of certain aquatic insects experience faster population declines, while tolerant organisms such as oligochaeta and some gastropods are becoming more dominant (Feng et al.
, 2.
Experimental lake ecosystem studies showed that simultaneous exposure to polystyrene and copper microplastics altered predator-predator zooplankton ratios, with a 45% decrease in the abundance of sensitive large daphnia and a proportional increase in the proportion of more tolerant rotifers(Tang et al.
This shift has a cascading effect on the entire food web, altering predator-prey dynamics and energy transfer between trophic levels.
Changes in community composition due to exposure to microplastics and heavy metals can disrupt ecosystem function through the loss of key species and fundamental shifts in trophic structures.
Species that are sensitive to microplastic contamination, such as filter feeders and primary PUTRI ET AL consumers, experience significant population declines, while more tolerant or opportunistic species tend to experience proliferation (Jeong et al.
Marykate & Kate, 2.
This shift leads to community homogenization and a decrease in functional diversity, where species with different functional traits are replaced by species with similar characteristics, resulting in reduced functional redundancy and decreased ecosystem stability (Cavalcante et al.
, 2.
The loss of key species such as ecosystem engineers or keystone predators can result in cascading effects that spread throughout the food web, altering habitat structure predator-prey interactions (Sanders & Frago, 2.
Disruptions to community composition further have an impact on fundamental ecosystem processes such as primary productivity, nutrient cycling, and energy flow.
A decrease in phytoplankton diversity and changes in species dominance can reduce the efficiency of photosynthesis and primary production by 20-40%, impacting the entire trophic level above it (Krumhardt et al.
, 2.
Changes in the composition of decomposers and decomposing microorganisms disrupt the cycle of nutrients such as nitrogen and phosphorus, leading to the accumulation of organic matter and altered nutrient stoichiometry that can trigger eutrophication or local oligotrophication (Duhamel, 2.
In addition, changes in the community structure of zooplankton and benthos alter bioturbation and sediment mixing patterns, which impacts oxygen penetration in sediments and biogeochemical processes at the sediment-water interface (Chakraborty et al.
, 2.
These systemic disturbances ultimately reduce the resilience of ecosystems to other environmental stressors and the ability to recover after disturbances, creating negative feedback loops that can result in regime shift or ecosystem collapse.
CONCLUSION
The sources of microplastics to the aquatic environment are diverse, including plastic waste, urban runoff, wastewater treatment effluents, agricultural activities, fishing equipment, ship paints, and atmospheric transportation.
The main factors affecting the fate of microplastics in the .
hotodegradation, transport, and interactions with biotic factors such as biofilm colonization.
The adsorption of heavy metals in microplastics involves several interactions, complex formation .
, ion exchange, and surface precipitation.
Adsorption efficiency is affected by environmental conditions such as pH, salinity, and dissolved organic matter.
The desorption of heavy metals from microplastics in aquatic organisms is affected by specific physiological conditions such as changes in pH in the digestive tract, digestive enzymes, bile acids, and the gut microbiota environment.
Once desorpated, the metal can be absorbed through the intestinal epithelium, gill cells, or penetration through the cuticle.
There are several major entry routes of microplastics and heavy metals into aquatic organisms.
Direct consumption, gills, cuticle and integument penetration, and cellular Simultaneous microplastics and heavy metals triggers a variety of biological responses, oxidative stress .
ncreased ROS), disruption of the antioxidant defense system.
DNA damage, and epigenetic disorders.
Histopathological damage to the gills, digestive tract, and detoxifying organs such as the hepatopancreas and liver.
Impaired growth and development, reproduction, and behavioral Changes in population demographic structure, shifts in community composition, food chain disruptions, and changes in biogeochemical Long-term exposure to a combination of microplastics and heavy metals can lead to .
Changes in population structure and dynamics, with selective pressures that benefit individuals with higher pollutant tolerances and potentially reduce genetic diversity.
Shifts in the composition of aquatic communities, with sensitive species experiencing faster population declines, while tolerant organisms become more dominant.
Disruption of energy transfer between trophic levels and heavy metal bioaccumulation in the food chain.
Degradation of ecosystem services, including fishery products, carbon sequestration, water purification, and recreational value.
Recommendations to address the complex impacts of microplastics and heavy metals in waters, policies include: .
strengthening regulations to restrict primary microplastics .
, in cosmetic and textile product.
and heavy metal industrial wastes, .
circular economy-based waste management with advanced filtration technologies .
uch as nanomembranes or biocha.
in wastewater treatment plants.
On the research side, priorities include: .
molecular toxicology studies to understand the synergistic mechanisms of microplastic-heavy metals at the cellular and epigenetic levels, .
development of pollutantabsorbing materials .
uch as hydrogels or engineered microbe.
that are effective in various environmental conditions, .
ecosystem modeling to predict long-term impacts on community structure and ecosystem services, and .
naturebased remediation tests .
hytoremediation, constructed wetland.
that are integrated with the water restoration policy.
CREDIT AUTHORSHIP CONTRIBUTION
STATEMENT
Adinda Kurnia Putri: Writing Ae original draft.
Conceptualization.
Writing Ae review & editing.
Yenni Arista Cipta Ekalaturrahmah:
Conceptualization.
Methodology.
Supervision.
Writing Ae review & editing.
Ahmad Ahmad: Data curation.
Conceptualization.
Writing Ae review & Moh Shoheh:
Conceptualization.
Methodology.
Supervision.
ACKNOWLEDGMENT
The author would like to express his appreciation to the Universitas Jenderal Soedirman and Universitas PUTRI ET AL Islam Madura, for their support and facilitation during this research.
ETHICS APPROVAL
No ethical approval was needed for this study.
FUNDING
The authors declare that no funds, grants, or other support were received during the preparation of this CONFLICT OF INTEREST
The authors declare no conflict of interest
DATA AVAILABILITY STATEMENT
The data that support the findings of this study are available from the corresponding author upon reasonable request.
REFERENCES