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• Effect of use and decontamination on the performance of surgical masks and respirators. • Breathability and filtration tests were used to evaluate used and decontaminated surgical masks and respirators. • Severe acute respiratory syndrome coronavirus-2 was inactivated by oven decontamination of respirators following work shifts. • Oven decontamination (75 °C, 45 min) is safe and feasible in hospitals. The coronavirus disease 2019 pandemic increased global demand for personal protective equipment (PPE) and resulted in shortages. The study evaluated the re-use of surgical masks and respirators by analysing their performance and safety before and after reprocessing using the following methods: oven, thermal drying, autoclave, and hydrogen peroxide plasma vapour. In total, 45 surgical masks and 69 respirators were decontaminated. Visual integrity, air permeability, burst resistance, pressure differential and particulate filtration efficiency of new and decontaminated surgical masks and respirators were evaluated. In addition, 14 used respirators were analysed after work shifts before and after decontamination using reverse transcription polymerase chain reaction (RT-PCR) and viral culturing. Finally, reprocessed respirators were evaluated by users in terms of functionality and comfort. Oven decontamination (75 °C for 45 min) was found to be the simplest decontamination method. Physical and filtration assays indicated that all reprocessing methods were safe after one cycle. Oven decontamination maintained the characteristics of surgical masks and respirators for at least five reprocessing cycles. Viral RNA was detected by RT-PCR in two of the 14 used respirators. Four respirators submitted to viral culture were PCR-negative and culture-negative. Reprocessed respirators used in work shifts were evaluated positively by users, even after three decontamination cycles. Oven decontamination is a safe method for reprocessing surgical masks and respirators for at least five cycles, and is feasible in the hospital setting. [ABSTRACT FROM AUTHOR]

Natural dyes have become an alternative option of interest for textile dyeing. The selection of native species as a natural dye can make its use feasible and enhance local biodiversity. In the present study, the extract of Croton urucurana Baill. bark, which is native to Brazil, was investigated as a natural textile dye. The extract showed a reddish-brown color and the presence of tannins. The extract was characterized by physicochemical methods and optimization of the dyeing process was determined by factorial design 23. The dyed fabrics were evaluated for color fastness to light, wash, rubbing and perspiration. They showed colors between beige and reddish-brown and had good fastness properties. Antibacterial activity assessment was performed on the extract and fabrics and UV protection was evaluated in the fabrics. The wastewater generated from the dyeing process was also characterized. It exhibited high biochemical oxygen demand and chemical oxygen demand, in addition to a large amount of dissolved iron and aluminum, when these metals were used as a mordant in the dyeing process. On balance, the extract of C. urucurana has the potential to be employed as a textile dye. • Analysis of C. urucurana bark extract showed the presence of tannin-based colorants. • C. urucurana bark extract was used to dye cotton and wool in beige to reddish brown shades. • The 2³-statistical experimental design method gave the optimized dyeing method. • Wastewater analysis indicated that treatment is needed before effluent releases. [ABSTRACT FROM AUTHOR]