Impact of Microplastics on Global Public Health: A Systematic Review and Meta-Analysis

Background: Microplastics (MP(s)) are an emerging environmental contaminant with growing concerns about their potential impact on human health. These particles, measuring less than 5 mm, are pervasive in the environment and have been detected in food, water, air, and human biological tissues. Despite increasing awareness, limited studies explore MP(s) exposure and its health risks. Research remains sparse on the breakdown of larger plastic fragments in biological systems and their long-term effects. Standardized exposure assessment methods, harmonized effect size reporting, and regulatory interventions are urgently needed. Methods: This systematic review and meta-analysis synthesize current evidence on human MP(s) exposure pathways, associated health risks, and knowledge gaps. Following PRISMA 2020 guidelines, we systematically searched multiple databases, including PubMed, Scopus, Web of Science, Embase, and Cochrane CENTRAL, to assess the extent of MP(s) exposure and its possible health implications. Results: Findings suggest widespread exposure through ingestion of food and water contamination, inhalation of airborne MP(s), and potential dermal absorption. Toxicological studies in animal models indicate that MP(s) can induce oxidative stress, metabolic dysfunction, immune dysregulation, and endocrine disruption. However, direct human health effects remain unclear due to methodological limitations, variability in exposure assessment, and a lack of long-term studies. Emerging research highlights concerns regarding neurological toxicity, reproductive health effects, and atmospheric transport mechanisms. Conclusions: The study analyzes the impact of MP(s) on public health, emphasizing the necessity for regulation and methods to limit its effects on ecosystems and humans. The findings highlight the importance of developing uniform guidelines for healthy persons, given the diversity in reported studies and the lack of existing guidelines. This global issue needs immediate action. Future research should prioritize longitudinal human studies, improved plastic detection techniques, and risk characterization frameworks to understand the public health implications of plastic exposure.