Exposure and inhaling of microplastics: An evidence of cause of cancer

Microplastics are defined as plastic particles less than 5 millimeters in diameter and can be categorized as primary and secondary microplastics. Microplastics are widely distributed in oceans, freshwater, soil, atmosphere, food chain and living organisms. Micro(nano) plastics enter the human body through the food chain, leading to their accumulation in the body. Different types of microplastics have been found in human placenta, meconium, breast milk, blood, and feces. The ingestion of microplastics may lead to impaired physiological functions in humans. Micro-and nanoplastics can serve as a source of carcinogenic or mutagenic substances, potentially causing DNA damage that can lead to carcinogenesis, the development of cancerous tumors. Currently, much remains unknown about the specific mechanisms of toxicity of micro(nano)plastics to living organisms, especially human cells. Although there are still many challenges to the direct application of micro(nano)plastics in cancer therapy, their unique physicochemical properties provide new ideas for cancer treatment. Plastics are highly persistent in nature due to which their degradation occurs at a slower rate and their accumulation at a faster pace. Plastics comprise polymers such as polyethylene (PE), polystyrene (PS), polypropylene (PP), polyethylene terephthalate (PET) and polyvinyl chloride (PVC). They are distributed across the aquatic systems, land surface, inside biological organisms, human consumables and even in the air.