The Abundance and Characteristics of Microplastics in the Sediments of the Progo River of Yogyakarta, Indonesia

Microplastics may pollute water bodies and endanger living things. The Progo River, one of the longest rivers crossing Yogyakarta Province, has been used as a source for drinking water for residents. However, plastic waste as a source of microplastics is tremendously high in this river. The objective of this study is to analyze the abundance and characteristics of microplastics in the sediments of the Progo River. Sediment sampling was administered in December 2019 at six stations in the upstream, midstream, and downstream rivers. The results showed that all sediment samples from upstream to downstream of the Progo River were found to contain microplastics with an abundance range of 209.37 to 1173.25 particles kg -1 . The highest microplastic abundance was found in the downstream area of 645.34 405.94 particles kg -1 , followed by the midstream of 480.23 174.09 particles kg -1 , and the upstream part of 276.85 73.70 particles kg -1 . Microplastics in the Progo River sediments both in the upstream, midstream, and downstream areas are dominant in size of 100 -500 m, fibers, and transparent in color. The type of polymer identified in each sample is polyester which is widely used for textile fibers due to the discharge of the residents' laundry washing water into the river. The Progo River, which is one of the top 20 dirtiest rivers globally, has a high abundance of microplastics after Jakarta and Karimun Jawa's rivers. Seeing the high number of microplastic abundance, the Indonesian government must immediately include microplastic parameters to regulate environmental quality standards.