Ovarian toxic effects of micro- and nanoplastics (Review)

Microplastics and nanoplastics (MNPs) have become widespread contaminants with notable impacts on reproductive health. MNPs have been found in human specimens, including follicle fluid, causing concerns regarding their negative impact on female fertility. The present review aimed to comprehensively examine the ovarian deleterious impacts of MNPs, and to analyze their toxicological mechanisms, impact on folliculogenesis and oocyte quality, transgenerational effects and influencing factors. Previous evidence suggests that MNPs can trigger oxidative stress, inflammatory responses, disruption of endocrine function, programmed cell death, endoplasmic reticulum stress, membrane structural damage, epigenetic modifications and DNA lesions in the ovary, resulting in impaired folliculogenesis, disrupted steroidogenesis and reduced reproductive capacity. The present review emphasized the impact of the MNP polymer type, size and surface characteristics on ovarian reproductive toxicity, and highlights some knowledge gaps that require attention, providing a reference for deeper understanding and mitigation of MNPs-induced ovarian toxicity.