Establishing a standard-basis for the characterization of marine microplastic-pellets

Abstract

Plastic pellets are small granulated microplastics with diameter of approximately 1-5 mm, which are considered as emerging pollutant in aquatic environment. However, the literature provides a poor database for classification and standardization of plastic pellets, impairing the comparison of environmental impacts assessed by several studies. Thus, in this work, a classification related to pellet characteristics was proposed in order to establish a standard of identification. Four sampling surveys were carried out in the Pecém-CE port area (northeastern coast of Brazil). The pellets were characterized according to its size, shape, transparency, and color.  From the characterization of the 1,411 pellets collected, granules with different morphologies were observed. Most classes of pellets had light colors (white 37%, yellow 22% and amber 12%). The classification of the granules resulted in a catalog with 160 classes, divided into blocks. The standardization of the characteristics of the pellets in classes, provided a documentation of the types of granules produced and found near the port area, making it possible to quantify and characterize the granules manually and with the naked eye. This type of classification can be used anywhere in the world as a tool to assist research on the presence of pellets in the marine environment and the impacts caused by them.