Quantitative and qualitative determination of microplastics in oyster, seawater and sediment from the coastal areas in Zhuhai, China

Microplastics as a new class of environmental contaminants have become the hot issue of global concern. We conducted quantitative and qualitative experiments to investigate microplastics in oyster, seawater and sediment along the Zhuhai coastline. The soft tissues of oysters were digested with potassium hydroxide (10%) and hydrogen peroxide (30%), seawaters and sediments with hydrogen peroxide (30%) to degrade organic matter, and analyzed using a digital camera, optical microscopy and micro-ATR-FTIR. The abundance of microplastics were in the range of 0.14?7.90 n/g in oysters (wet weight), 10.00?27.50 n/L in seawaters and 0.053?0.26 n/g in sediments. The fiber and fragment shape, black color, 101?500 ?m of size and polyethylene composition were all classified as the major constituents of microplastics. The level of contaminants in oysters was correlated to those in their surrounding environments. Therefore, oysters may serve as a promising sentinel species for the indication of microplastic pollution in the coastal zone of Zhuhai.

Automated summary

Microplastics have emerged as a new class of environmental contaminants, with oysters serving as potential sentinel species for indicating microplastic pollution levels in their surrounding coastal environments. The study conducted in Zhuhai coastline revealed the presence of microplastics in oysters, seawater, and sediments, with polyethylene composition, fiber and fragment shapes, black color and specific size ranges being identified as major constituents.