1Rosane Rezende de Souza Giuliani, 2Felipe Santos Teixeira Martiniano, 3Nicole Mioto Medeiros, 4Lorenzo Francesco Giuliani, 5Leocadia Felix de Araujo, 6Rafaela Gonçalves Bueno, 8Carlos Henrique Batista Figueiredo de Mendonça, 6,7Thiago Augusto Rochetti Bezerra
1Graduated in Medicine. Head of the Hematology Service at the Portuguese Beneficent Society of Santos, São Paulo, Brazil. Professor of Hematology at the University of Ribeirão Preto (UNAERP), São Paulo, Brazil.
2Resident physician in Internal Medicine, Beneficência Portuguesa Hospital of Santos, São Paulo, Brazil.
3Graduated in Medicine from the University of Vale do Sapucaí (Univás), Minas Gerais, Brazil. Hematology and Hemotherapy at the Amaral Carvalho Hospital, Jaú, São Paulo, Brazil. Physician at the Beneficência Portuguesa Hospital in Santos and professor at the University of Ribeirão Preto (UNAERP), São Paulo, Brazil.
4Resident physician. Specialist in Anesthesia, Resuscitation, Intensive Care, and Pain at the University of Rome “La Sapienza,” Rome, Italy.
5Graduated in Medicine from the Federal University of Fronteira Sul – UFFS. Passo Fundo, Rio Grande do Sul
6Medical student at the University of Ribeirão Preto, Guarujá campus.
7Doctor of Medical Sciences, Ribeirão Preto School of Medicine, University of São Paulo.
8Graduated in Medicine from the Federal University of Roraima, Brazil
ABSTRACT
This systematic review aimed to analyze the effects of microplastics on human physiology, emphasizing toxicity mechanisms and health risks. The search was conducted in the PubMed, Scopus, Web of Science, Embase, and SciELO databases, covering studies published between 2000 and 2025. Forty-eight studies were included that addressed the presence of microplastics in human tissues and fluids, their pathophysiological mechanisms, and possible clinical outcomes. The results showed that microplastics are present in blood, placenta, and reproductive tissue samples, demonstrating their ability to cross biological barriers and interact with cells and organelles. The most consistent mechanisms described involve oxidative stress, systemic inflammation, mitochondrial dysfunction, endocrine dysregulation, and reproductive changes. In vitro and in vivo assays indicated increased production of reactive oxygen species, activation of inflammatory cytokines, and DNA damage. Recent evidence also suggests effects on the gut microbiota and fetal development, with a higher microplastic load observed in placentas from premature births. Despite advances in research, there are significant methodological limitations, such as a lack of standardization in detection techniques, control of environmental contamination, and a scarcity of longitudinal studies evaluating the dose-response relationship. It is concluded that microplastics represent an emerging contaminant with potential systemic and multi-organ impact, posing a growing concern for public health. More stringent environmental policies, population biomonitoring, and the development of standardized analytical methodologies are needed to more accurately assess the biological effects of these particles. Understanding of the risks associated with microplastics must be expanded through interdisciplinary approaches that integrate toxicology, cell biology, epidemiology, and environmental health.
KEYWORDS
microplastics; toxicity; inflammation; oxidative stress; endocrine dysfunction; human health.
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