Inflammatory Impact of Microplastics on Human Lung Cells

Overview

Micro- and nanoplastics are an air- and waterborne pollutant. They are carried globally; high levels have been found in dust in Tehran, snow samples in the Pyrenees, and in ice samples from the Arctic. Textiles pose a commonplace source of airborne microplastics — laundry effluent alone composing an estimated 35% of primary microplastic pollution in the ocean. Clothes also shed fibers into the air through daily wear, leading to a large concentration of indoor microplastics. When the clothes are made of synthetic fiber, plastics are released. Airborne microplastics pose a new threat to human lung health since they can embed in the alveoli and increase the risk of emphysema and cancer. The effect of microplastic particles on human lung epithelial cells was investigated. Based on a literature search of similar studies, it was hypothesized that microplastics would lead to inflammation. Polystyrene spheres of 0.50 μm diameter were added to A549 cell culture media at concentrations ranging from 0.05 μg/mL to 100 μg/mL. Cell counts, a trypan blue viability assay, and photomicroscopy was performed every 24 hours for a 72-hour trial. By 48 hours of exposure, the cells exposed to more than 25 μg/mL of microplastics became visibly more fibroblastic in their appearance. Extracellular vacuoles also appeared, and large masses of cell fragments and adsorbed microparticles formed. It is thus likely that the reaction was inflammatory in nature. These results support the possibility that airborne microplastics pose a potential significant harm to human lung health. TEXAS