Discharge of microplastics fibres from wet wipes in aquatic and solid environments under different release conditions.

This study warns regarding the possibility of microplastics (MPs) release from wet wipes and further in the environment and examines the potential associated risks. The exposure of humans to MPs during cleaning, and their discharge into wastewater treatment processes through flushing in toilets/basins was simulated by rubbing wet wipes on hands and immersing them in water, respectively. Wet wipes can be stored in a waste bin and subsequently disposed of through waste treatment or directly disposed in aquatic environments. The released MPs were identified and quantified using Fourier transform infrared spectroscopy. The released MPs were in the fibre form, and their major component was polyester. A higher number of MP fibres (693-1066 p/sheet) was released when the wet wipe was exposed to the aquatic environment compared to rubbing the wet wipe on hands or solid materials (180-106 p/sheet) or both. In particular, wet wipes in the wet state released the highest number (1966 p/sheet) of MP fibres. Unexpectedly, the least number of MP fibres was released by rubbing them on the hands/solid (180-200 p/sheet). Most fibres (>90%) were more than 100 μm, and those above 300 μm accounted for more than 40%-60% of the total number of detected MP fibres. This implies that long MP fibres released into the environment could disrupt the health of the aquatic ecosystem owing to their bioaccumulation, retention time, intestinal toxicity, and the transfer of persistent organic matter to aquatic organisms.