Release of microfibers from surgical face masks: an undesirable contributor to aquatic pollution

The worldwide usage of surgical face masks (SFM) has increased rapidly during the COVID-19 pandemic. Its degradation possibly produces billions of microplastics (MPs) in the environment. To quantify the release of microfibers (MFs), unused SFM were treated with eight different aqueous solutions, each with five replications in two categories, i.e., freshwater (FW) treatments [800 mL FW, 40 mL of 95% alcohol + 800 mL FW, 40 mL of 30% H2O2 + 800 mL FW, and 4 g sodium dodecyl sulfate (SDS) + 800 mL FW], and saltwater (SW) treatments (800 mL SW, 40 mL of 95% alcohol + 800 mL SW, 40 mL of 30% H2O2 + 800 mL SW, and 4 g SDS + 800 mL SW) at 25 °C for 60 days. The predominant MFs disposed from SFM were transparent and sized between 1.0 to < 0.5 mm. The mean highest amount of MFs observed was 4,911.3 (1-day) and 6,180.24 (30-day) in sodium dodecyl sulfate (SDS) mixed with SW, and 7,269.7 (60-day) in SDS with FW. The greatest number of MFs released per day was 275 (SDS in SW), followed by 193 (SDS in FW). The results indicated that if different kinds of water are mixed with detergent (SDS), it could accelerate the disposal of MP, whereas SW has considerably higher ability to release more MFs in a shorter time period compared to FW. Furthermore, this study implied that the inappropriate dumping of SFM could unfortunately escalate the preexisting MP pollution in the aquatic environment, which could negatively affect the aquatic living beings.