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. 2021 Mar 10;196:117033. doi: 10.1016/j.watres.2021.117033

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Fig 4 — Shows SEMs images 1.S, 2.S and 3.S (face masks 3, 7c and 4) and a corresponding elemental map (1.M, 2.M and 3 M). 1.M coloured fuchsia representing carbon on a fiber and particle, 2.M is coloured green to represent silica on grains and 3.M is Purple indicating the presence of lead found on some of the grains.