An investigation into the aging mechanism of disposable face masks and the interaction between different influencing factors

In the natural environment, a symphony of environmental factors including sunlight exposure, current fluctuations, sodium chloride concentrations, and sediment dynamics intertwine, potentially magnifying the impacts on the aging process of disposable face masks (DFMs), thus escalating environmental risks. Employing Regular Two-Level Factorial Design, the study scrutinized interactive impacts of ultraviolet radiation, sand abrasion, acetic acid exposure, sodium chloride levels, and mechanical agitation on mask aging. Aging mechanisms and environmental risks linked with DFMs were elucidated through two-dimensional correlation analyses and risk index method. Following a simulated aging duration of three months, a single mask exhibited the propensity to release a substantial quantity of microplastics, ranging from 38,800 ± 360 to 938,400 ± 529 particles, and heavy metals, with concentrations from 0.06 ± 0.02 μg/g (Pb) to 29.01 ± 1.83 μg/g (Zn). Besides, specific contaminants such as zinc ions (24.24 μg/g), chromium (VI) (4.20 μg/g), thallium (I) (0.92 μg/g), tetracycline (0.51 μg/g), and acenaphthene (1.73 μg/g) can be adsorbed significantly by aged masks. The study elucidates pivotal role of interactions between ultraviolet radiation and acetic acid exposure in exacerbating the environmental risks associated with masks, while emphasizing the pronounced influence of many other interactions. The research provides a comprehensive understanding of the intricate aging processes and ensuing environmental risks posed by DFMs, offering valuable insights essential for developing sustainable management strategies in aquatic ecosystems.