The Threat of Micro-/Nanoplastics to Male Fertility: A Review of the Data and the Importance of Future Research

Micro-/nanoplastics (MNPs) and their associated endocrine-disrupting chemicals (EDCs) have emerged as pervasive environmental pollutants, with growing concern for their impact on male reproductive health. In this review, we synthesize the findings from twenty-one peer-reviewed studies published between January 2019 and March 2025, selected through a structured literature search conducted in accordance with the SANRA guidelines. Emphasis was placed on studies examining the cellular effects of MNPs and EDCs on Germ, Leydig, and Sertoli cells. The literature indicates multiple mechanisms of testicular toxicity, including degradation of the blood testis barrier, disruption of signaling pathways critical for spermatogenesis and hormone synthesis, induction of oxidative stress and inflammation, and structural and genetic damage to testicular tissues. These data, primarily derived from in vitro and animal models, not only highlight significant biological disruptions but also underscore the limitations in extrapolating results to human physiology. Differences in exposure routes, dosages, and species-specific responses present challenges to direct translation to humans. This review concludes that further human-centric research that mimics real-life exposure and impacts is essential to assess chronic, low-dose exposures and bridge the gap between experimental data and real-world reproductive outcomes, ultimately informing public health strategies and guiding future investigations into the reproductive risks posed by MNPs and EDCs.