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Images to show the original texture of the fabrics composing each face mask (a, d, g, l, o and r panels) and a scanning electron microscopy image (SEM) of a typical fiber from each fabric plucked from face mask before the laundering (b, e, h, m, p and s panels) and collected in nylon bags after laundering (c, f, i, n, q and t panels). PA = polyamide; PL = polyester; PP = polypropylene; PU = polyurethane; CO = cotton; Sf = surgical face mask (PP fabric).
