Microplastics and Impaired Male Reproductive Health - Exploring Biological Pathways of Harm: A Narrative Review

Microplastics (MPs), pervasive environmental pollutants, have emerged as significant health hazards with growing evidence linking them to impaired male reproductive health. MPs can enter the human body through ingestion, inhalation, and dermal absorption, and once internalized, can induce oxidative stress, inflammation, endocrine disruption, and cellular damage leading to impaired male reproductive health. The present narrative review explores the biological pathways through which MPs impair male reproductive health, focusing on their direct and systemic effects. A comprehensive literature search spanning up to February 2025 was conducted across electronic databases, including PubMed, Scopus, Web of Science, and Google Scholar. Search terms such as "microplastic exposure," "male infertility," "male reproductive health", "oxidative stress," "endocrine disruption," "spermatogenesis," "inflammation," and "reproductive toxicity" were employed to identify relevant studies published in peer-reviewed journals, books, and reputable conference proceedings. Inclusion criteria were limited to articles written in English that focused on the biological pathways linking MP exposure to impaired male reproductive health. Priority was given to review articles, original research papers, and meta-analyses. Extracted information was systematically organized to provide a narrative synthesis. Current evidence suggests that MPs may impair male reproductive health through mechanisms like oxidative stress, hormonal disruption, inflammation, and cellular damage. However, the lack of human studies highlights the urgent need for robust research to clarify their impact on human male infertility. Furthermore, this review underscores the necessity for continued research to elucidate molecular mechanisms, inform preventative strategies, and guide regulatory policies addressing MP pollution and its health implications.