Authors: Susmita Sarker Bristi, Rafiqul Islam
Categories: MANAGEMENT AND PRODUCTION, Microplastic, Poultry, Source and bioaccumulation, Transmission pathway, Public health consequence
Source: Poultry Science
Authors: Susmita Sarker Bristi, Rafiqul Islam
•Microplastics enter poultry via feed, water, litter, environment and processing equipment.•MPs can accumulate in different organs such as gastrointestinal tract, liver, kidneys, spleen, muscles, etc.•Exposure disrupts gut microbiota, causes oxidative stress and impairs growth, meat quality and egg production.•Contaminated poultry products pose potential health risks to humans.•Key strategies such as reducing plastic use, improving detection methods, raising awareness and implementing proper safety regulations should be adopted to minimize associated risks.
Humans have domesticated and raised several poultry species such as chicken, duck, goose, turkey, guinea fowl, ostrich, etc., for the purpose of egg and meat production to fulfill the nutritional demand for animal protein (Abadula et al., 2022). As one of the most intensively farmed livestock sectors, globally the poultry industry has faced numerous challenges over the past few decades, including disease outbreaks, antibiotic resistance resulting from indiscriminate antimicrobial use and the accumulation of drug and pesticide residues in eggs, meat and offal (Castro et al., 2023). Another emerging concern for both the poultry industry and consumers is the contamination of poultry products and byproducts with microplastics (MPs), resulting from exposure through contaminated feed ingredients, drinking water, litter, and the surrounding environment (Bouwmeester et al., 2015). Human activities, particularly industrial production, generate substantial quantities of plastic materials into the environment each year. Over time, these plastics can degrade through UV radiation, natural weathering and other environmental processes, leading to the formation and dispersal of MPs, which contribute to widespread environmental contamination and pose significant risks to both animal and human health (Luo et al., 2016; Jiao et al., 2019; Zhong et al., 2021; Liu et al., 2022; Liu et al., 2023; Zhao et al., 2023; Siddiqui et al., 2023).
Plastic particles are classified based on their those larger than 5 mm are termed macroplastics, particles between 1 and 5 mm are mesoplastics, those ranging from 0.1 µm to 1 mm are MPs and particles smaller than 0.1 µm are defined as nanoplastics (Koehler et al., 2015). Due to their small size, MPs are widely dispersed in air, soil, water, living organisms and even in seafood and beverages, highlighting their potential to enter the food chain and affect both animals and humans (Rao, 2019; Lee et al., 2019; Sucharitakul et al., 2021; Zou et al., 2023). The more alarming fact is that MPs have been detected in animal and fish feed (Muhib and Rahman, 2023; Olmo and Holman, 2025). Previous studies investigating the impacts of MP exposure in different species and demonstrated their detrimental effects on host health. For example, Jin et al. (2019) reported that environmental exposure to MPs in mice led to gut microbial imbalance, impaired intestinal barrier function and disruptions in amino acid and bile acid metabolism. Recent studies have shown that MPs can negatively affect behavior, survival, and reproduction, impair sperm and oocyte quality, reduce body size and motility, and induce inflammation, intestinal damage, neurotoxicity, oxidative stress, genotoxicity, and disruptions in fat and energy metabolism (Çobanoğlu et al., 2021; Goodman et al., 2022; Lee et al., 2025). However, MPs pose threats not only to animal health but also to human health, as Leslie et al. (2022) reported detecting MPs in 80% of the individuals tested. Although the environmental and biological impacts of MP exposure have received considerable attention, most research has focused on model and aquatic animals (Jin et al., 2019; Papp et al., 2024), while studies on the effects of MPs on poultry health remain very limited.
Poultry species are often used to assess the negative impacts of environmental pollutants due to their high chance of exposure and sensitivity. In addition, poultry species constitute a major source of animal protein for human consumption, making them relevant for both animal health studies and public health considerations. Previous studies have detected MPs in broiler feces, providing clear evidence that poultry ingest these particles (Wu et al., 2021). Growth retardation, delayed sexual maturation, increased incidence of epididymal cysts and alterations in the gut microbiome have been reported in various poultry species, including chickens, ducks and quails (Monclús et al., 2022; Zou et al., 2023; Gu et al., 2025). Therefore, to ensure animal welfare, safeguard consumer health, and mitigate potential risks, comprehensive research is needed to identify the sources of MP exposure in poultry and feed, as well as to understand their possible effects (Cauwenberghe and Janssen, 2014; Wu et al., 2021). The origins, transmission routes and negative impacts of various MP sources to poultry products are inadequately studied. Currently, there remains a significant gap in toxicological data specifically related to poultry, a limited comprehension of exposure pathways in intensive poultry production systems and inadequate information regarding the transfer, retention and possible accumulation of MPs in consumable tissues and eggs. Consequently, present evaluations of human exposure via poultry products predominantly depend on extrapolations from models that are either non-poultry or non-terrestrial in nature. In this context, the present review aims to examine the sources and health impacts of MPs in poultry. Additionally, it will provide mechanistic insights into how these MPs can be transferred from poultry to humans, posing significant health risks, and discuss the challenges in addressing this issue.
MPs can be categorized into two primary MPs, which are intentionally manufactured for specific applications, such as pellets or microbeads in personal care products and laundry items; and secondary MPs, which result from the degradation of larger plastic materials under environmental conditions (Andrady, 2011; Cole et al., 2011; Hidalgo-Ruz et al., 2012). Plastic debris usually comes from plastic materials and undergo breakdown by temperature, UV radiation and other factor, finally ends up as MPs. MPs originate from anthropogenic, marine, terrestrial and atmospheric sources, frequently interacting within intricate environmental systems.
Anthropogenic sources are directly associated with human activity, encompassing both intentional (primary) and unintentional (secondary) MP generation. The rising incidence of uncontrolled and open waste dumping has led to food packaging materials, primarily composed of plastics, being carelessly discarded in the environment. Food packaging materials have been recognized as an additional source of MPs (Jadhav et al., 2021). In certain regions, expired food items, including biscuits and bread, are utilized as animal feed. Plastic residues in expired packaged foods may act as exposure sources for poultry (Cornelis et al., 2021).
MPs from marine habitats come from human activities or the degradation of plastics in marine ecosystems. Ocean-based sources contribute significantly to marine MP pollution. Approximately 60–80% of global waste comprises plastic, with nearly 10% of worldwide plastic production entering the oceans, where decomposition may require several hundred years (Avio et al., 2017). Annually, around 8 million tons of plastic are predicted to reach the oceans (Erni-Cassola et al., 2019).
Riverine transport is considered a significant conduit for MPs to enter marine habitats (Zhang et al., 2016). For example, the Pearl River is a recognized contributor of MPs in beach sediments in Hong Kong (Fok and Cheung, 2015). MP prevalence has been documented in regions as isolated as Antarctica (Cincinelli et al., 2017). MPs which come from fertilizers have been identified in runoff water, posing a pollution risk to neighboring water bodies and ecosystems (Thompson et al., 2024).
MPs can originate on land and then build in soil, make their way into freshwater systems, or, through a variety of transport modes, end up in marine ecosystems; this is known as "terrestrial sources of MPs." Evidence indicates the presence of MPs in mulched soil, with an average abundance of 571 particles per kilogram (Zhou et al., 2020). A recent study indicates that the use of plastic mulch for over 12 years in Spanish farmlands resulted in an average of 2242 ± 984 MPs kg⁻¹ in the soil (van Schothorst et al., 2021). Tire wear particles, road markings, building materials, and trash from cities also make a big difference. Stormwater runoff often carries these things into nearby lakes and rivers.
Recent research has identified airborne MPs as a significant and under-recognized pathway. MPs are released into the atmosphere from multiple sources, including synthetic fabrics, tire wear from vehicles, household products, waste incineration, construction materials, sewage sludge, landfills, and abrasive powders (Akanda et al., 2025). MPs can be conveyed by wind and deposited in distant locations by dry or wet deposition. MP fibers in the atmosphere originate from textiles, while non-fibrous particles primarily originate from decaying packaging materials, worn-out tires, paints, and industrial pollutants (Wright et al., 2020). MPs may accumulate in soil organisms, including earthworms (Huerta Lwanga et al., 2017). Most of the MPs in the air were from synthetic fabrics, and researchers found that daytime MP collections were twice as large as nighttime ones (Acharya et al., 2021; Blackburn and Green, 2022).
In 2021, global poultry production showed a substantial increase compared to previous years, reaching an estimated 137 million metric tons (FAO, 2021). Global food security, nutrition and economic development largely depend on poultry production. Meat and eggs, rich in important amino acids, vitamins (including B12) and minerals like iron and zinc, are easily available sources of high-quality animal protein. Poultry production is increasingly jeopardized by the rising prevalence of MPs in the environment as well as in contaminated feed, drinking water and bedding materials. MPs can contaminate poultry products, such as meat and eggs from various birds, resulting in a series of consequences that require comprehensive research and monitoring. However, poultry products and byproducts can become contaminated with MPs through various pathways.
Feed represents one of the primary sources of MP exposure in poultry. The presence of MPs in water and soil facilitates their entry into the food chain. Research has shown that poultry can ingest MPs indirectly through pecking at contaminated soil or debris, or directly from commercial feeds that becomes contaminated during production, packaging, storage or transportation (Picó & Barceló, 2019).
In many regions, poultry and livestock graze on crop residues after harvest, often ingesting residual plastic fragments mixed with feed, which later appear in manure as smaller degraded particles (Beriot et al., 2021; Wu et al., 2021). In 2019, Wu et al. (2021) detected micrplastics (9.60 × 10^2^ ± 1.09 × 10^2^ particles/kg feed) in commercial layer feed. Poultry can also be exposed to MPs through contaminated drinking water originating from agricultural runoff or environmental pollution as well as from airborne dust and deposition on feed, litter and birds. Over time, plastic equipment such as feeders, drinkers, and cages may release MPs due to wear and degradation (Jadhav et al., 2021). Studies have reported extensive MP contamination in animal feed components, including fishmeal and soybean meal, across several countries, with common polymers such as polyethylene, polypropylene, polystyrene, polyamide, polyethylene terephthalate, and polyvinyl chloride (Beriot et al., 2021; Wu et al., 2021; Walkinshaw et al., 2022; Maganti and Akkina, 2023). MPs have also been identified in chicken, turkey and other meat samples from retail markets, particularly polyethylene terephthalate, polypropylene, polystyrene, and polyvinyl chloride (Huang et al., 2020; Velebit et al., 2023). Additional sources include hydroponic fodder, degraded feed packaging and plastic mulching materials (Urbina et al., 2020; Xu et al., 2022; Ramachandraiah et al., 2022). As natural water bodies serve as drinking sources for poultry, MPs from freshwater ecosystems can easily enter the food chain (Koutnik et al., 2021; Kumar et al., 2021; Lu et al., 2021). Research on terrestrial birds is less extensive compared to that on aquatic species; nonetheless, terrestrial birds are crucial components of the food web within terrestrial ecosystems.
MPs infiltrate the ecosystem and environment from multiple sources, including plastic waste from poultry farming operations and packaging materials (EFSA, 2016; Oliveri Conti et al., 2020). According to Huerta Lwanga et al. (2017), a large number of MPs could get up in hens' food supply if people tossed plastic trash around in their yards. The raw materials of feed, such as cereals and vegetables, originate from agricultural soils and are subject to atmospheric exposure, with roots and trunks, particularly leaves, readily adsorbing MPs and enter into animal body (Yin et al. 2021). Due to wind and precipitation processes, airborne MPs can accumulate with dust, hence exacerbating MP pollution (Patchaiyappan et al. 2021; Wang et al. 2021). MPs can infiltrate poultry via multiple environmental channels (Fig. 1) especially during the raising and farming phases. After that, they are ingested or inhaled via poultry species.Fig. 1Pathways of microplastic contamination in poultry and subsequent transfer to humans.Fig
Plastic processing utensils and cutting boards found in slaughterhouses and kitchens are one major route. Particles of plastic, primarily polyethylene, are expelled during mechanical processes such as chopping, grinding and cutting, and they have the potential to stick to or become embedded in the poultry flesh and offal. Plastic cutting boards have been identified as the source of MP contamination in raw cut chicken sourced from Middle Eastern markets, with levels reaching up to 0.25 mg MP/g chicken (Habib et al., 2022). That means, during processing of bird or poultry, MPs from cutting board can enter into poultry products and byproducts. Moreover, the utilization of plastic gloves, packaging sheets and conveyor belts can exacerbate contamination.
Research indicates that MPs can accumulate in the gastrointestinal tract (GIT) and organs of chickens, potentially impacting the quality of byproducts utilized in animal feed, fertilizer, or industrial uses (Table 1). There is a chance that MP-laden earthworms could wind up in chicken excrement if chickens consume them. One study identified average microplastic concentrations in edible tissues, specifically breast and leg muscles, at 4.80 ± 2.86 and 1.60 ± 1.81, respectively and underscores the potential for microplastic exposure through quail meat, emphasizing the associated consumption risks (Doğan et al., 2024).Table 1MPs detected in different organs or droppings of different poultry species worldwide.Table Country/RegionSpecies (Organs/droppings)Sources/Exposure typesDetection LevelsPolymer types detectedParticle sizeKey findingsReferencesPakistanChicken(Crop and Gizzard)Poultry feed∼1,227 MPs detected across sampled birdsPolyvinyl chloride (51.2%), low-density polyethylene (30.7%), polystyrene (13.6%) and polypropylene (4.5%)50-500 µmMPs were present in digestive tract; dominant polymers included PVC, LDPE, PS; potential dietary exposure risk highlightedBilal et al., 2023aPakistanDuck(Crop and Gizzard)River Water∼2033 MPs detected across sampled ducksLow-density polyethylene (39.2%), polyvinyl chloride (28.3%), high-density polyethylene (22.7%), polystyrene (6.6%), co-polymerized polypropylene (2.5%) and polypropylene (0.7%)50-500 µmMPs were commonly found in birds’ digestive systems and nearby water, showing a serious risk to wildlife and the environmentBilal et al., 2023bChinaChicken(Droppings)Poultry Feed6.67 × 10^2^ ± 9.90 × 10^2^ MPs/kg of droppingsPolypropylene (29.17%), polyethylene (31.25%), polyethylene terephthalate (14.58), polypropylene + polypropylene resin (6.25%), polypropylene + polyethylene (8.33%) and Cellulose + polypropylene resin (10.42%)-Severe MPs contamination was found in poultry farms, mainly fibers and fragments, with manure application acting as a major sourceWu et al., 2021IranChicken(Droppings)--Polyethersulfone, polytetrafluoroethylene, polystyrene, polyethylene terephthalate, polyethylene (21.95%), polypropylene (21.95%)-MPs were detected in over 70% of samples, with blue fibers made of polyethylene and polypropylene being the most prevalent formsMohammadi et al., 2025IndonesiaDuck(GIT)Feed11-49 MPs/duckPoly-n-butyl methacrylate, polyester, polyethylene terephthalate, nylon and polyvinyl chloride100 μm - > 5 mmMPs were found in the duck GIT, likely originating from contaminated feedSusanti et al., 2021MexicoChicken(Gizzard and droppings)Terrestrial food web129.8 ± 82.3 MPs/g droppings(*>*5 mm; 84% MaPs) in crop,(16 % microplastics, 5 mm) in gizzard,(microplastics, 1 mm) in feces0.1-1 mmHumans may be exposed to high levels of microplastics either by eating gizzards directly or indirectly through microplastics transferred from chicken digestive systems into tissues(Huerta Lwanga et al. (2017)BrazilJapanese Quail(GIT)Experimental oral ingestion11 and 22 MPs/day/bird for 9 daysPolystyrene3293.45 µm ± 60.34 µmNaturally aged MPs cause biochemical changes in quail and are broken down and excreted, enabling birds to spread microplastics in the environmentde Souza et al., 2022AustraliaJapanese Quail(Gizzard and dropping)Experimental oral ingestion5-10 MPs/birdPolypropylene3–4.5 mmIngestion of environmentally relevant MPs may delay growth and sexual maturity but does not impact survival or population levels in Japanese quailRoman et al., 2019ChinaChickenEnvironmental exposure--Reduced growth, impaired antioxidant capacity & gut microbiota disruptionLi et al., 2022bTurkeyQuail(GIT, muscle)34 - 61 MPs/birdPolyethylene, polyvinyl stearate67.07±29.89 μmMPs were found in quail organs and edible tissues, with highest levels in the intestinesDoğan et al., 2024
Prior studies have shown that MPs may be transferred from soil to earthworms and subsequently to chicken, with a measured concentration of 129.8 ± 82.3 particles per gram feces (Huerta Lwanga et al., 2017). MPs detected in poultry intestines and gizzards sourced from wet markets in the Philippines have been attributed primarily to contaminated chicken feed (Leon et al., 2022). Chen et al. (2023) administered MPs to chickens; however, 33 other polymers, including polyethylene terephthalate, polystyrene and polyamide, were identified in the chicken muscles, particularly in the breast muscles.
The distribution of MPs in poultry tissue has been the subject of numerous studies. MPs have been detected in the gastrointestinal tract, liver and muscle tissues of poultry (Jha and Mishra, 2021; Horvatits et al., 2022). MP contamination was identified in the gastrointestinal samples of local ducks from intensive animal husbandry, with an average of 27 to 49 particles per individual (Susanti et al. 2021). In Shanghai, China, a total of 17 birds were detected, and 364 particles from the digestive tract of 16 birds were identified as micro-artificial waste, ranging in size from 0.5 to 8.5 mm (Zhao et al. 2016). A recent assessment identified various MP shapes, sizes, and polymers in the intestines of ducks raised in an intensive system in Indonesia (Susanti et al., 2021). A more plausible hypothesis is that MPs enter the duck intestinal tract through their meal rather than the agricultural method (Susanti et al., 2021) due to their farming system. Limited research has been conducted on chicken, duck, and quail; however, other bird meats like as turkey, pigeon, and goose, which are very popular, have not been studied to detect MPs.
The toxicological effects of MPs on poultry health present a complex issue with implications for organ function, immunity and even reproduction. Once ingested through contaminated feed, drinking water or bedding, MPs disrupt the balance of gut microbiome with reduced microbial diversity and impaired nutrient absorption (Lu et al., 2018; Li et al., 2023a). Such disturbances in gut health can reduce overall performance and increase susceptibility to disease. Evidence suggests that they negatively influence the cardiovascular system in chickens (Zhang et al., 2022b) and interfere with normal liver function by disturbing metabolic processes within the gut-liver axis (Yin et al., 2023). These findings highlight how MPs are not confined to local effects in the digestive tract but can also affect different vital organs and compromise broader physiological systems. Therefore, the negative impacts of MPs on poultry health and production require immediate attention and also need to be documented in order to plan effective strategies to combat this challenge. Despite the significance of MPs, very limited data are available on the adverse effects of MPs in the vital organs of poultry, as most existing studies have focused primarily on aquatic or marine organisms which can however provide a broader insight into this emerging issue worldwide.
The liver is a key target of MP toxicity as the accumulation of MPs in organs interferes with normal metabolic and detoxification processes. MPs induce inflammation and oxidative stress and thus cause hepatic dysfunction in marine invertebrates and fishes (Hu and Palić, 2020; Labcom et al., 2024, Hayat et al., 2025). They also cause severe liver damage by disrupting the gut barrier, promoting microbial translocation and triggering tissue necrosis in chicken (Yin et al., 2023). Study on quail showed that MPs affect both the liver and lung, with liver weight reduction indicating compromised metabolic capacity and reduced body weight gain (Lu et al., 2018; You et al., 2025). Additionally, Chen et al. (2024) demonstrated that the accumulation of MPs in the livers of female breeding ducks led to hepatic fibrosis, highlighting long-term structural and functional damage.
The kidneys are also highly vulnerable to MP-induced oxidative and mitochondrial stress. Meng et al. (2022) found that chickens exposed to polystyrene MPs (5 μm) for forty-two days developed kidney impairment, oxidative stress and mitochondrial dysfunction, particularly at exposure levels of 10-100 mg/L. In Muscovy ducks, MP exposure resulted in severe mitochondrial damage in kidney tissue (Zou et al., 2024). This was accompanied by increased apoptosis, evidenced by the upregulation of pro-apoptotic markers (Bax, Caspase-3, Caspase-9) and downregulation of the anti-apoptotic marker Bcl-2 (B-cell lymphoma 2), particularly under oxidative stress conditions.
Recent studies have also revealed that MPs can lead to severe splenic damage. Guo et al. (2024) demonstrated that MPs compromise mitochondrial structure and function, initiate apoptosis through the mitochondrial pathway, and trigger redox imbalance-induced ferroptosis, resulting in splenic tissue damage in chicken. Similarly, Zhang et al. (2024) reported that MPs damaged splenic microstructure, disrupted cellular organization and caused inflammation in Japanese quail. These alterations were accompanied by oxidative stress, increased malondialdehyde and reactive oxygen species levels, and reduced pro-inflammatory cytokines. Moreover, MPs activated the p38 mitogen-activated protein kinases pathway, leading to splenic cell death through TNF (Tumor Necrosis Factor) signaling in chicken (Abd El-Hack et al., 2024).
Since the gut microbiota is responsible for both monitoring and carrying out intestinal function, outside influences always have an impact (Fig. 2). The gut microbiota exhibits inherent stability due to the interactions and plasticity within the microbial community (Li et al., 2022a). Certain factors, particularly MPs, can disrupt the intestinal environment and influence the survival of the microbiota (Lu et al., 2019). In these circumstances, the abundance or type of microorganisms may alter to adapt to the new intestinal environment, potentially resulting in the disruption of gut microbial homeostasis. Deng et al (2020a) found that MP exposure in mice leads to gut microbiota dysbiosis, metabolic abnormalities, increased intestinal permeability and inflammation. Similarly, microplastic exposure has been shown to reduce colonic mucin production, alter inflammatory responses, and induce gut microbial dysbiosis in mice (Sun et al., 2021), as well as decrease antioxidant enzyme activities and increase oxidative stress, leading to renal damage in rats (Ijaz et al., 2024). According to earlier investigations, MP exposure can reduce gut microbiota Chao1 (Chao1 richness estimator) and ACE (Abundance-based Coverage Estimator) indices in chickens, leading to dysbiosis and decreased microbial abundance (Lu et al., 2018).Fig. 2Mechanism of microplastic induced gut dysfunction in poultry.Fig
MP exposure also leads to a reduction in short-chain fatty acids (SCFA) producing bacteria such as Oscillibacter and Blautia in chicken (Li et al., 2023a). SCFAs play significant roles in reducing cholesterol levels, regulating energy intake and mitigating inflammation (He et al., 2020; Magliocca et al., 2022; Carretta et al., 2021). In duck, excessive exposure to MPs disrupted the equilibrium of gut microbiota, exacerbating hepatic metabolic dysfunction and inflammatory responses through the activation of the LPS/TLR4/NF-κB pathway (Zhou et al., 2025).
MPs cause growth retardation and ultimately poor body weight gain in poultry. For instance, Zhang et al. (2024) reported that the Japanese quails exposed to MPs had shorter and lighter bodies compared to the control group. In another study, You et al. (2025) showed that MPs, in aggregate, diminished the body weight of quail. Hens exposed to polyethylene via feed exhibited a reduction in body weight (Li et al., 2023b); however, hens administered varying doses of MPs through drinking water demonstrated no significant changes in body weight or myocardial weight (Zhang et al., 2022b). After a 5-week exposure to MPs, birds have been shown to lose up to 4.04% of their average body weight, indicating a measurable impact on growth performance and overall physiological condition (Zhang et al., 2024). On the contrary, three controlled studies assessing final body weight found no significant effects from MP exposure at any of the concentrations examined (Meng et al. 2022; Zhang et al. 2022a; Yin et al. 2023). Similarly, Zou et al. (2023) reported no impact of MPs on the daily feed consumption of chickens. Therefore, the impact of MPs on body weight gain still remains inconspicuous and needs further comprehensive investigation.
MPs negatively affect muscle physiology and decrease meat quality. Chen et al. (2023) reported that MPs influence metabolism, induce oxidative stress and neurotoxicity of skeletal muscle, alter metabolomic profile and thus, decrease meat quality. Despite the aforementioned negative effects, the chickens consuming polystyrene MPs unexpectedly demonstrated a measurable increase in their total body weight and skeletal muscle mass (Chen et al., 2023). MPs also affects gene expression linked to neural function which in turn regulates muscle growth and overall meat quality. However, research on the effects of MPs on muscle development and meat quality remains very limited, and further studies are needed to clarify the underlying mechanisms.
MPs disrupt ovarian folliculogenesis by interfering with hormonal signaling pathways critical for follicle development (Ilechukwu et al., 2022) and adsorbing endocrine-disrupting chemicals like bisphenol A (BPA), which mimic or antagonize natural hormones, consequently impacting ovulation and corpus luteum formation (Chae and An, 2020). According to Nahiduzzaman et al. (2025) this results indicate potential effects on poultry species regarding a reduction in egg production.
Reproductive health is a significant factor affected by MP exposure in poultry. MPs disrupt the endocrine system and thus, hormonal balance which result in reproductive complications, including modified egg production, fertility disorders and developmental anomalies in hen (Ullah et al., 2023; Sharma and Vidyarthi, 2024). MPs damage the testicular tissue of male chickens and cause oxidative stress and inflammatory infiltration (Hou et al., 2022). Studies indicate that the ingestion of MPs may pose risks to the reproductive systems of birds (de Souza et al., 2022; Roman et al., 2019). For example, Japanese quail chicks that exhibited plastic consumption showed a higher frequency of male epididymis intraepithelial cysts compared to those that did not consume plastic (Roman et al., 2019).
Animal-based protein sources constitute approximately two-thirds of overall protein consumption worldwide (Pasiakos et al., 2015; Hoy et al., 2021). Considering an average daily protein consumption of 83 g, poultry egg or meat intake is approximated at 12.5 g per day. Consumers may inadvertently ingest MPs when consuming poultry products, potentially leading to the accumulation of these substances in their bodies. The potential exposure levels of MPs in humans vary depending on dietary habits, as well as the regulatory frameworks and safety measures implemented across different regions worldwide. Reported contamination levels range from 0.03 ± 0.04 to 1.19 ± 0.72 particles per gram in chicken meat (Abd El-Hack et al., 2025), 0.16–0.48 particles per gram in quail meat (Doğan et al., 2024), and approximately 11.7 particles per gram in chicken eggs (Amanatidou et al., 2024). The estimated average dietary exposure of U.S. adults from the consumption of various protein sources exceeds 11,000 MP particles per year (Milne et al., 2024). MPs can enter the human body across three distinct cutaneous contact, inhalation and ingestion. Upon entering the body, they subsequently integrate into the biological chain naturally (Lehel and Murphy, 2021). Studies demonstrate that MPs can be assimilated by the gastrointestinal system and disseminated throughout the human body (Schwabl et al., 2019). After dietary exposure, human uptake is feasible, as demonstrated by the ability of synthetic particles smaller than 150 μm to penetrate the gastrointestinal epithelium in mammals, leading to systemic exposure (Campanale et al., 2020). Scientists estimate that merely 0.3% of these particles will be absorbed, with an even smaller fraction (0.1%) comprising particles larger than 10 µm, which may penetrate both organs and cellular membranes, as well as traverse the blood–brain barrier and placenta (Barboza et al., 2018).
Exposure concentrations are predicted to be low; however, data regarding MPs in the environment remain limited (Campanale et al., 2019) and in poultry products are none due to the analytical and technical challenges associated with their extraction, characterization and quantification from environmental matrices. It is essential to conduct risk evaluations and investigations of MPs in the human body resulting from meat consumption.
Polystyrene and polyvinyl chloride have been demonstrated to generate hazardous monomers that contribute to carcinogenesis and reproductive deformities in humans (Wang et al. 2016). Forte et al. (2016) conducted a study demonstrating that PS nanoparticles influenced cell viability, inflammatory gene expression, and cell shape in human gastric cancer epithelial cells.
The health implications of ingesting MPs via poultry products remain inadequately understood. MPs are known to accumulate in the tissues and organs of humans (Sorci and Loiseau, 2022). This accumulation can result in inflammation, oxidative stress and various cellular responses (Hu and Palić, 2020). The potential physiological effects of MP ingestion on human health indicate possible disruptions in gastrointestinal functions and metabolic processes (Horton et al., 2017; Zhang et al., 2023). The full extent of these health risks remains under investigation, yet the potential bioaccumulation of MPs in human tissues is increasingly concerning (Kumar et al., 2022; Kutralam-Muniasamy et al., 2023). Winiarska et al. (2024) noted that MPs pose a threat to both humans and chickens due to the toxic compounds and bacteria they contain. While there is extensive information regarding the health risk and intake of MPs through inhalation and the consumption of seafood and fish, data on the uptake of plastics, particularly MPs, by humans through the ingestion of poultry products is limited. Moreover, no international agency (e.g., WHO, FAO, JECFA) or national regulator has established formal dietary intake limits or tolerable intake values for MPs in food as of 2025. Regulatory efforts remain focused on research, monitoring frameworks, and mitigation of MP pollution rather than setting safety thresholds for MPs in specific foods. Key evidence gaps include the lack of standardized analytical methods and limited data on poultry products, which hinder accurate exposure quantification and cross-study comparisons. In addition, insufficient information on particle size distribution (especially nanoplastics), toxicokinetics, dose-response relationships, long-term health outcomes and the effects of food processing prevents robust human health risk assessment of dietary MPs exposure from poultry products.
One of the primary challenges is reducing the use of plastics in daily life and eliminating any kind of plastic materials in poultry feed production or meat processing plants. It is not possible to prevent environmental MP pollution without actively reducing plastic usage. Another potential constraint is our very limited capacity to detect MPs in minimal quantities within the sample (Huang et. al., 2020). Bilal et al. (2023a) highlight that MPs represent a significant global issue because of their toxicity to living organisms; however, the effects of their toxicity on chickens and humans remain unclear. Consequently, the existing method's sensitivity for detecting MPs exhibited potential for enhancement (Huang et al., 2020). Therefore, studies should be focus not just on prevalent plastic polymers but also on other polymer types that are widely present in various environmental matrices, necessitating more comprehensive testing. In many underdeveloped or developing countries, the contamination of poultry meat and eggs with MPs remains undetermined.
In order to guarantee consumer safety, policymakers are currently contending with the issue of regulating MP levels in food (Rainieri and Barranco, 2019). It is essential to ensure that consumers are informed about the potential hazards associated with MPs in poultry products in order to enable them to make informed decisions that may reduce their exposure to MPs (Deng et al., 2020b; Oleksiuk et al., 2022). Policy-driven measures should be established and rigorously enforced in poultry feed production and meat or byproduct processing. Additionally, awareness among poultry farmers should be raised to minimize MP contamination (Usman et al., 2022). There is an insufficient comprehension of the exact methods by which MPs pass from poultry to human tissues and organs. This impedes the capacity to precisely evaluate the exposure level and associated danger. It may be difficult to accurately predict the precise processes and consequences of MPs consumption by all poultry species and their indirect influence on human health. It may be challenging to effectively incorporate numerous perspectives due to the interdisciplinary nature of this task. Future research should encompass comprehensive toxicological assessments to elucidate the causes and effects of exposure, alongside meticulous monitoring of MP levels in poultry products.
This paper reviews recent findings regarding MPs in poultry species. A comprehensive MP transfer path was illustrated, and the behavior and impact of MP were analyzed. Animal items like meat and milk can introduce harmful chemical pollutants into the human diet, but MPs in food can cause physiological stress, inflammation and even the relocation of these pollutants. Consequently, we ascertain that the influence of antimicrobial peptides in conventional poultry may pose a rising risk to human health, food safety, and the environment. Nevertheless, the inadequate information accessible hinders the ability to conduct a precise evaluation. Therefore, it is recommended for future studies to focus on standardized analytical protocols and controlled exposure experiments that accurately represent real-world farming scenarios. It is crucial to focus on the detection of MPs in edible tissues and eggs, along with the long-term effects of low-dose exposure that are pertinent to consumers.
The authors received no funding for this manuscript.
Susmita Sarker Bristi: Writing – original draft, Resources, Formal analysis, Data curation. Rafiqul Islam: Writing – review & editing, Writing – original draft, Visualization, Validation, Supervision, Software, Resources, Data curation, Conceptualization.
The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.