Effects of surgical masks exposed to different weathering conditions on behavior and growth of whiteleg shrimp (Litopenaeus vannamei)

The COVID-19 pandemic has led to a surge in the global demand for surgical masks. These masks can be a new source of plastic pollution in the ocean. Discarded masks often end up in coastal areas, undergoing weathering and microbial attachment, eventually settling on the seabed and potentially impacting benthic marine life. This study focuses on whiteleg shrimp (Litopenaeus vannamei), a benthic species native to coastal areas and known to ingest microplastics. We exposed shrimp to new surgical masks, sun-exposed surgical masks, and seawater-soaked surgical masks, and studied shrimp-mask interactions and the effects of chronic exposure on shrimp behavior and growth. Initial encounters with seawater-soaked masks resulted in reduced activity levels. After a 28-day exposure period, shrimp subjected to sun-exposed masks demonstrated lower activity levels. In terms of feeding behavior, shrimp in contact with seawater-soaked masks showed reduced interest in food. No significant effects were observed on shrimp growth or microplastic bioaccumulation. These findings indicate that contact with or chronic exposure to weathered surgical masks significantly impacts the behavior of whiteleg shrimp.