MICROPLASTIC fibers from FACE MASKS lodged in human lungs The study published on March 29 in Science of The Total Environment (https://bit.ly/3MCMOgn) looked at the lung tissue of 11 patients undergoing thoracic surgery. Using spectroscopy, the study authors analyzed the different kinds of materials present in the samples and found 12 kinds of microplastics. Of the 12 microplastics found in the samples, polypropylene (PP) and polyethylene terephthalate (PET) were the most prevalent substances. PP consisted of 23 percent of microplastics found in all lung tissue samples, while PET followed at 18 percent. Plastic resin was the third most prevalent at 15 percent. Furthermore, tissue samples taken from patients’ lower lungs had the highest concentration of microplastics. Some of the microplastic fragments and fibers found measured two millimeters long. “Human lung tissue samples were typically comprised of PP, PET and resin … with fibers being more prevalent than fragments,” the researchers wrote. PP fabric, which is most commonly used to make surgical masks, is made from thermoplastic polymers that can be easily handled at high temperatures. Aside from PP, other materials derived from thermoplastic polymers such as polystyrene, polycarbonate, polyethylene or polyester are also used for face masks. “The abundance of [microplastics] within samples … supports human inhalation as a route of environmental exposure. [They] are designed to be resilient. It had previously been suggested that inhaled [microplastics] are likely to bio-persist and possibly accumulate within a lung environment, showing resilience to degradation,” concluded the study authors. “The knowledge that [microplastics] are present in human lung tissues can now direct future cytotoxicity research to investigate any health implications associated with [microplastic] inhalation.”