Paper Title
Determination of Microplastics in Sediments of the Water Body - Caño Juan Angola in Cartagena de Indias -Colombia

Abstract
The plastics industry in 2018 reached a global production of 360 million tons. Due to baddisposition, mass consumption, quick disposal and the lack of sustainable recycling and reuse policies, large volumes of different types of plastic residues have been generated, which reach water bodies through runoff among other bad anthropogenic practices. As time passes, they become microplastics due to their resistance to degradation and end up as a source of food for aquatic animals, besides representing a source of contamination of water bodies. Among 17 to 29 million metric tons of this mismanaged waste end up in aquatic ecosystems, making the problem of microplastic pollution in freshwater bodies, as serious as, in marine environments. Considering the above, the aim of this study was to determine the presence of microplastics in sediments from geo-referenced points from Caño Juan Angola, an urban natural channel located in the city of Cartagena de Indias, using the density difference methodology presented by the National Office of Oceanic and Atmospheric Administration (NOAA). The determination was carried out in two stages: the first consisted of pretreatment of the sediment, which was dried at 70 °C for 72 hours until it was free of moisture, reduced in size and purified using 30% hydrogen peroxide to eliminate organic matter from the sediment; the second, consisted of developing the process of extraction of microplastics by applying the analytical method of density separation, using a supersaturated solution of reactive NaCl; 5 extractions were performed in order to improve the efficiency of the process; the extracted samples were analyzed by FTIR. In conclusion, it was possible to identify the presence of compounds related to plastics such as polyethylene terephthalate (PET) from plastic bottles and aliphatic compounds related to hydrocarbons; Therefore, the analytical method of density difference can be recommended for the determination of microplastics in sediments, taking into account that it was possible to determine the presence of two types of microplastics in the sediments of the case study. Keywords - Microplastics, Density Difference, Sediments.