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Contamination of disposable medical masks has become a growing problem globally in the wake of Covid-19 due to their widespread use and improper disposal. Three different mask layers, namely the outer layer, the meltblown (MB) filler layer and the inner layers release three different types of microplastics, whose physical and chemical properties change after prolonged environmental weathering. In this study, physical and chemical changes of mask microplastics before and after aging were characterized by different characterization techniques. The toxic effect and mechanism of aged mask microplastics on Escherichia coli (E. coli) were studied by measuring the growth inhibition of mask microplastics, the change in ATPase activity, the change in malondialdehyde content and reactive oxygen species production, and the release of the chemical composition of exopolymeric substances (EPS). The microplastics of the aged MB filter layer had the most significant inhibitory effect on E. coli growth, reaching 19.2 % after 36 h. Also, under the influence of mask microplastics, ATPase activity of E. coli was inhibited and a large amount of EPS was released. The chemical composition of EPS has also changed. This study proposed the possible toxicity mechanism of mask microplastics and the self-protection mechanism of E. coli, and provided a reference for future research on the toxic effects of mask microplastics on environmental organisms., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Background: Along with COVID-19 pandemic, India has faced an outbreak of COVID-19-associated mucormycosis (CAM). Due to restricted availability of amphotericin B during this outbreak, clinicians were forced to use posaconazole or isavuconazole preparations as first-line or alternate therapy in many patients. We planned an early monitoring of posaconazole trough level while using delayed release (DR) tablet as first-line or alternate therapy., Objectives: Primary objective of the study was to determine percentage of patients achieving arbitrarily decided therapeutic posaconazole levels (≥1.2 μg/ml) after using standard dosages of posaconazole. Secondary objective was to identify potential factors associated with sub-therapeutic posaconazole levels., Methods: We performed retrospective chart review of the hospitalised patients, who received posaconazole DR tablet as first-line or alternate therapy to treat CAM during outbreak period (March 1 to May 31, 2021). High-performance liquid chromatographic (HPLC) method was used to measure trough level of posaconazole., Results: Posaconazole serum levels of 29 patients were analysed, who received posaconazole DR tablet. Majority (n = 23) were male with the median (range) age 53 (24-86) years. The mean (SD) posaconazole level was 1.66 (0.76) μg/ml. Sub-therapeutic posaconazole trough level was observed in 7 (24.1%) patients. Relatively younger patients were associated with lower posaconazole level (p = .046). Except two patients, all the patients tolerated posaconazole well., Conclusions: The study supports the posaconazole trough level measurement on day 4 while using posaconazole DR tablet as first-line or alternate therapy to treat mucormycosis during limited supply of amphotericin B., (© 2021 Wiley-VCH GmbH.)

The global panic caused by COVID-19 has continued to increase people's demand for masks. However, due to inadequate management and disposal practice, these masks have, unfortunately, entered the environment and release a large amount of microplastics (MPs), posing a serious threat to the environment and human health. Understanding the occurrence of mask waste in various environments, release of mask-origin MPs, and related environmental risk is essential to mask-waste management in current and future epidemic prevention and control. This paper focuses on the global distribution of mask waste, the potential release of waste-origin MPs, and the impact on the environment. Specifically, the physical and chemical properties of polypropylene (the most common plastic material in a mask), which show a high adsorption capacity for heavy metals and organic pollutants and play a role as a support for microbial growth, were extensively reported. In addition, several important issues that need to be resolved are raised, which offers a direction for future research. This review focuses on the essentiality of handling masks to avoid potential environmental issues. [ABSTRACT FROM AUTHOR]