As industrialization expands and human activities increase, so does plastic production. Plastics, which do not degrade easily in the environment, eventually break down into tiny particles called microplastics and nanoplastics (MNPs). These particles can enter the human body through ingestion, inhalation, or skin contact, accumulating in various tissues over time. Inhalation is particularly concerning because these small particles can reach deep into the lungs, especially the alveoli. This review brings together studies that explore the effects of MNPs on the respiratory system, covering research on animals, humans, and cell cultures. The findings reveal that exposure to MNPs can lead to significant harm in live organisms and laboratory models. A key factor in this damage is oxidative stress and the production of reactive oxygen species (ROS) caused by MNPs, which play a central role in developing lung diseases. Oxidative stress is also linked to other issues, such as DNA damage, loss of cell membrane integrity, and inflammation. This review offers important insights for researchers interested in the health impacts of emerging pollutants and lung-related diseases.