Microplastics and human health: Exposure pathways, toxicological impacts, and sustainable risk management

Microplastics in drinking water: Addressing human health risks and removal strategies

Background: Microplastics (MPs) have emerged as significant environmental contaminants increasingly detected in drinking water. Originating from plastic waste, textiles, and industrial effluents, MPs can infiltrate water systems and resist conventional treatment processes. Their small size and ability to carry toxic substances such as plasticizers, heavy metals, and persistent organic pollutants raise serious concerns regarding human health and water safety. Methods: This study employed a narrative review approach by synthesizing literature published between 2021 and 2025 from PubMed, Dimensions AI, and ScienceDirect. The review examined the sources of MPs in drinking water, associated human health risks, detection methods, removal technologies, and existing regulatory frameworks. Findings: The review found that MPs in drinking water pose considerable health risks through chemical leaching, bioaccumulation, and physical damage. Smaller particles, particularly nanoplastics, are difficult to detect and can bypass conventional filtration systems. Exposure to MPs is associated with endocrine disruption, gastrointestinal disorders, neurodegenerative diseases, and other long-term health impacts, especially among vulnerable groups such as children and pregnant women. Advanced treatment technologies, including nanofiltration, reverse osmosis, and electrocoagulation show potential for effective removal, although economic and operational limitations hinder large-scale implementation. The study also identified major policy gaps, including the absence of standardized global regulations and safety thresholds for MPs. Conclusion: Microplastic contamination in drinking water represents a growing threat to public health and water quality management. Improved detection methods, stronger regulatory frameworks, advanced treatment technologies, and public health education are urgently needed to reduce exposure and ensure safer drinking water systems worldwide. Novelty/Originality of this article: This study provides a comprehensive and up-to-date synthesis of microplastic contamination in drinking water by integrating health risk assessment, detection challenges, treatment technologies, and policy analysis within a single review. It highlights critical gaps in regulation and emphasizes the need for global standardization and interdisciplinary solutions.

Plastic waste management and the emergence of microplastics as an integrated challenge involving sources exposure pathways health implications and circular solutions

Plastic pollution has emerged as a pervasive global environmental and public health challenge, affecting terrestrial and aquatic ecosystems across all spatial scales. Macro-, micro-, and nanoplastics enter food webs through ingestion, inhalation, and trophic transfer, posing distinct yet interconnected toxicological and physiological risks to wildlife and livestock, while potential implications for human health are still being actively investigated. Macro plastics primarily cause physical injuries, gastrointestinal obstruction, starvation, and mortality in marine and terrestrial animals, while microplastics act as vectors for chemical additives and pathogens, inducing oxidative stress, inflammation, and microbiome disruption. Nanoplastics, due to their small size and high surface reactivity, exhibit enhanced bioavailability, enabling cellular uptake and translocation across biological barriers in experimental systems, with studies indicating potential genotoxic and endocrine-disrupting effects. However, evidence regarding long-term human health outcomes remains limited and is still emerging. This review synthesizes current evidence on exposure pathways, biological impacts, and ecosystem-level consequences of plastic pollution, highlighting critical knowledge gaps related to chronic toxicity, mixture effects, and long-term health outcomes. This review uniquely integrates waste management system failures, toxicological mechanisms, and circular economy interventions to provide a systems-level synthesis of plastic pollution pathways from production to health outcomes. We further examine mitigation strategies through a circular economy lens, emphasizing source reduction, product redesign, extended producer responsibility, improved waste management, and policy coherence across scales. Integrating technological innovation with governance, behavioral change, and stakeholder collaboration is essential to curb plastic leakage and prevent secondary micro- and nano plastic formation. Overall, addressing plastic pollution requires systemic, science-based interventions that link environmental protection with human health objectives. Such integrated approaches directly support the achievement of Sustainable Development Goals 3 (Good Health and Well-Being), 12 (Responsible Consumption and Production), 14 (Life Below Water), and 15 (Life on Land), reinforcing the urgency for coordinated global action.

Microplastics and nanoplastics in humans: exposure pathways, biological mechanisms, and implications for health risk assessment

Abstract Microplastics (MPs) and nanoplastics (NPs) are ubiquitous contaminants, but their implications for human internal exposure, biological effects, and health risk assessment remain incompletely defined. Although many reviews summarize environmental occurrence and ecological impacts, fewer integrate human exposure pathways with mechanistic toxicological evidence and safety-relevant uncertainties. This review synthesizes evidence on inhalation, ingestion, and dermal exposure, emphasizing particle size, barrier interactions, translocation, and distribution. We examine experimental and clinical evidence describing oxidative stress, inflammatory signaling, epithelial barrier dysfunction, gut dysbiosis, immune activation, and endocrine interference associated with MP and NP exposure. Particular attention is given to distinguishing MPs from NPs in terms of cellular uptake, biodistribution, analytical detectability, and toxicodynamic behavior. We also discuss limitations in exposure assessment, including contamination bias, analytical detection limits, and harmonized reporting standards. Rather than focusing on environmental prevalence, this review highlights gaps in exposure quantification, dose-response relationships, chronic low-dose exposure, vulnerable populations, and co-exposure to plastic additives or adsorbed contaminants. An organ-specific risk perspective is integrated, emphasizing respiratory, digestive, immune, and systemic effects, as well as particle size, polymer type, exposure concentration, and human dose-response uncertainty. By synthesizing toxicological, analytical, and public health evidence, this review defines research priorities for risk assessment.

Microplastics and Nanoplastics in the Human Diet: Sources of Exposure, Bioavailability, Toxicokinetics, and Systemic Health Effects

Background/Objectives: Microplastics (MPs) and nanoplastics (NPs) have emerged as ubiquitous environmental contaminants resulting from the extensive production, use, and degradation of plastic materials. Human exposure occurs primarily through contaminated food and drinking water, with inhalation representing an additional important route. Growing concern has focused on the ability of these particles, particularly NPs, to cross biological barriers, enter the systemic circulation, and reach human tissues. The aim of this review was to summarize current evidence on dietary exposure to MPs and NPs, their gastrointestinal bioavailability and toxicokinetics, and their potential systemic health effects, with particular emphasis on organ-specific responses, underlying biological mechanisms, and the strength and limitations of the available evidence. Methods: A comprehensive narrative review of the scientific literature published between 2000 and 2026 was conducted using PubMed/MEDLINE, Scopus, Web of Science, and Google Scholar. Original research articles and review papers addressing dietary exposure, occurrence in food and drinking water, migration from food-contact materials, gastrointestinal absorption, translocation, biodistribution, bioaccumulation, elimination, molecular mechanisms, and potential organ-specific or systemic health effects were included. Publications without full-text availability, conference proceedings, editorials, commentaries, duplicate publications, and studies without relevance to human exposure or health were excluded. Results: Food, drinking water, beverages, and food-contact materials represent important sources of human exposure to MPs and NPs. Following ingestion, most larger particles are eliminated through the gastrointestinal tract, whereas smaller MPs and particularly NPs may cross biological barriers and potentially reach the systemic circulation and distant tissues. Experimental studies consistently identify interconnected biological responses involving oxidative stress, inflammation, mitochondrial dysfunction, barrier impairment, immune dysregulation, genotoxicity, apoptosis, and endocrine disruption. These mechanisms have been associated with alterations in the gastrointestinal, respiratory, cardiovascular, nervous, urinary, reproductive, endocrine, and skeletal systems and with biological processes relevant to carcinogenesis. However, most mechanistic evidence derives from in vitro and animal models, whereas human evidence remains limited and predominantly observational. Consequently, the extent to which these experimental findings translate into clinically significant effects in humans remains uncertain. Conclusions: Current evidence supports the biological plausibility of systemic effects associated with MNP exposure but is insufficient to establish causal relationships between chronic dietary exposure and specific human diseases. The detection of MNPs in human tissues and reported associations with pathological conditions should therefore be interpreted cautiously. Standardized analytical methods, improved characterization of realistic human exposure, and well-designed longitudinal epidemiological studies integrating quantitative exposure assessment with validated clinical outcomes are required to clarify dose–response relationships, long-term health effects, and the clinical significance of MNP exposure.

Microplastics as unexplored emerging contaminant: A challenge for food safety.

Microplastics and human health risks: toward evidence-based policy and regulation in the Philippines

Microplastics (MPs) have emerged as pervasive environmental contaminants with increasing relevance to human exposure and public health. While global evidence on MP occurrence and exposure is rapidly expanding, country-specific syntheses that translate environmental findings into policy-relevant insights remain limited. In the Philippines, no national policy explicitly mandates systematic monitoring or regulation of microplastics across environmental, food, or atmospheric systems. To address this gap, this qualitative meta-synthesis integrates evidence from Philippine studies examining MP occurrence across environmental matrices, biological samples, and experimental toxicological investigations to evaluate potential human exposure pathways and regulatory implications. Across multiple regions of the country, MPs are consistently detected in matrices directly associated with inhalation and dietary intake, including ambient air, road dust, freshwater and marine environments, and commonly consumed seafood and aquaculture products. Fibers and fragments dominate most environmental matrices, with polymers such as polyethylene, polypropylene, polyethylene terephthalate, and polyester frequently identified, indicating contributions from packaging materials, textiles, and urban plastic waste sources. Although direct epidemiological evidence linking MP exposure to human health outcomes remains limited, the convergence of widespread environmental occurrence, plausible exposure pathways, mechanistic evidence of toxicity, and food-chain contamination highlights the need for precautionary regulatory responses. This review provides a policy-oriented framework that emphasizes standardized monitoring protocols, upstream source-control strategies, the integration of microplastics into food safety systems, and the explicit recognition of inhalation pathways within national environmental and public health governance.