Adverse health effects and mechanisms of microplastics on female reproductive system: a descriptive review

Area of Science:

• Environmental Science
• Toxicology
• Reproductive Biology

Background:

• Microplastics (MPs), smaller than 5 mm, are prevalent environmental contaminants.
• MPs, including polystyrene (PS-MPs), exist in various forms and enter ecosystems, posing risks to wildlife.
• Previous research indicates MPs can cause reproductive toxicity in animals.

Purpose of the Study:

• To review the adverse effects of polystyrene microplastics (PS-MPs) on the female reproductive system.
• To elucidate the specific mechanisms and pathways through which PS-MPs induce reproductive toxicity.

Main Methods:

• Literature review of studies investigating PS-MPs and female reproductive health.
• Analysis of research detailing cellular and molecular impacts of PS-MPs exposure.
• Examination of effects on endocrine disruption and organ-specific toxicity.

Main Results:

• PS-MPs exposure linked to larger ovaries with fewer follicles, reduced embryo production, and lower pregnancy rates in mice.
• Hormonal imbalances and oxidative stress were observed, impacting fertility.
• Cell death (apoptosis, pyroptosis) in granulosa cells via NLRP3/caspase and Wnt pathways.
• Uterine fibrosis and endometrial thinning due to TL4/NOX2 activation.
• Negative impacts on ovarian function, oocyte maturation, and quality.
• Disruption of the hypothalamus-pituitary-gonadal axis in marine animals, affecting reproduction and offspring.
• Reduced fecundity and germ-line apoptosis.

Conclusions:

• Polystyrene microplastics pose significant threats to female reproductive health across species.
• Multiple cellular and molecular pathways are implicated in PS-MP-induced reproductive toxicity.
• Further research is crucial to understand the full scope of reproductive risks posed by microplastic pollution.