Effects of micro and nano plastics on renal health

Abstract

Research on microplastics (MPs) and kidney health is rapidly expanding, yet major knowledge gaps remain. Human exposure remains poorly characterized, with limited data on MPs levels in drinking water, food, indoor air, urine, blood, and kidney tissues. Most animal models rely on high-dose, short-term exposures, whereas studies employing environmentally realistic doses and long-term designs are required to evaluate links with chronic kidney disease and fibrosis. Mechanistic insights are also incomplete; the roles of ferroptosis, pyroptosis, and complement activation, as well as the influence of particle size, shape, polymer type, and surface charge, warrant further investigation. Co-exposures are another critical issue, as MPs act as vectors for heavy metals, persistent organic pollutants, and plastic additives, while also interacting with the gut microbiota and immune system. Clinical implications are particularly concerning: Dialysis fluids, intravenous solutions, and medical devices may represent unrecognized sources of exposure. Addressing these gaps will require multidisciplinary approaches, harmonized detection methods, and clinical monitoring to assess the burden and health consequences of MPs in vulnerable populations. This review underscores the kidney as a potential target organ for MP accumulation and highlights the urgent need for human biomonitoring.

Keywords: Microplastics; Kidney; Nephrotoxicity; Ferroptosis; Pyroptosis; Oxidative stress; Co-exposure; Dialysis; Environmental health

Core Tip: Microplastics and nanoplastics are emerging environmental contaminants capable of reaching the human kidney through ingestion, inhalation, and medical exposure. Experimental data reveal that microplastics accumulate in renal tissue, inducing oxidative stress, endoplasmic reticulum stress, inflammation, autophagy, and ferroptosis. Co-exposure with metals or plastic additives enhances nephrotoxicity, while early human findings confirm their presence in kidney tissue and dialysis fluids. This review integrates mechanistic, experimental, and clinical evidence, highlighting the kidney as a vulnerable target organ and calling for standardized detection methods, multi-omics approaches, and biomonitoring to assess the health burden of plastic exposure.