A Systematic Review on the Impact of Micro-Nanoplastics Exposure on Human Health and Diseases

Plastic production is continuously increasing worldwide for daily use. Micro-plastics and nano-plastics remain major emerging pollutants and threaten the environment, ecosystem, human health, and well-being. Micro-nanoplastics (MNPs) are also exposed to humans through cosmetics, inhalation, ingestion, drinking water, dietary sources, and drug formulations. Oral uptake is the major among the different exposure routes of MNPs to humans. After entry, it gets absorbed due to its nano size (˂100 nm) and easily distributed to all parts of the body through blood, affecting multiple organs, especially vital organs of the human body leading to severe diseases. It causes cancer, heart, liver, and kidney diseases, crosses the blood-brain barrier, and affects the brain. Its adsorption with protein leads to multi-layered corona formation in human blood plasma. MNPs interact with immune cells and induce pro-inflammatory mediators, inflammatory reactions, reactive oxygen species (ROS) production, and associated cytotoxicity. MNPs suppress T lymphocyte activity which results in a lack of immune regulation leading to autoimmune diseases. Hence, it is necessary to understand the impact of MNPs exposure on humans. Strict control measures for the production and use of plastics and developing appropriate strategies for safe disposal would prevent MNPs-mediated toxicity in humans.