161 Keynote: Characterising Microplastic Exposure and Hazards: Challenges and Opportunities

Abstract Plastic is the third most abundant manmade material on the planet. Whilst often considered durable, it sheds micro- and nanoscopic debris (‘microplastic’) to the environment, which contaminates water, dust, and food globally. Recently, microplastic has been reported in atmospheric deposition and airmasses around the globe, suggesting a complex cycle before it reaches its environmental – or biological – fate. Furthermore, the discovery of microplastic in ambient and indoor air has raised concern for public exposure via inhalation and potential impacts on health. In laboratory studies, exposure to high levels of certain types of microplastic can cause adverse effects, primarily oxidative stress, and metabolic disruption. However, there are critical physicochemical factors which govern both the fate and effects of inhaled material in the body and very little is known for microplastic. This talk will give an overview of the progress in plastic aerosol research, from early environmental measurements to analytical and data science advances to hazard characterisation. It will highlight challenges, knowledge gaps, and opportunities for research. As discussions for a proposed UN Treaty on Plastic Pollution develop and the rate of plastic production continues to grow, it is timely to consider microplastic exposure and its potential role in disease pathways.