Microplastics Exposure Impact on Lung Cancer—Literature Review

The ubiquitous environmental pollution with micro- and nano-sized plastic particles (MNPs) is a current and significant problem today. At the same time, lung cancer is responsible for the largest number of cancer-related deaths worldwide. Many research groups have investigated the relationship between lung cancer development and exposure to MNPs in recent years. Studies have demonstrated that these particles could enter the respiratory system in a variety of ways—both directly through inhaled air and through the bloodstream, and through internalization in the intestines and other digestive organs. Data regarding the possibility of their aggregation in the respiratory system, thyroid gland, and brain are also concerning, as the harmful effects of MNPs have been proven to depend on their concentration and exposure time. The primary response of cells to plastic particles is an increase in oxidative stress. This is generated both by the cell itself (especially macrophages) and induced by damage caused by mechanical damage to cellular organelles by MNPs. The consequences of MNP exposure can include metabolic disturbances, DNA damage, and mutations, ultimately inducing neoplastic transformation in healthy cells. This can lead to changes in tissue architecture and increase their susceptibility to other pathogens, such as pathogenic microorganisms or heavy metals. These, in turn, can be internalized along with MNPs, forming a corona surrounding them.