Investigation of Microplastic Contamination in Sediments, Water and Aquatic Biota in Lake Beratan, Tabanan Regency, Bali Province – Indonesia

Abstract

Microplastics (MPs) has become a very serious global threat, especially to the health of animals, humans and the environment. In this study we aim to investigate the contamination of MPs in sediment, air, and aquatic biota collected from the waters of Lake Beratan in Bali Province, Indonesia. Lake Beratan is one of the strategic areas that continues to develop as a tourist destination, agriculture and fisheries, as well as a source of water for daily needs.Sediment, water, and aquatic biota samples were collected from 4 stations that represent the Beratan Lake area. Each sample obtained was then followed by the pre-treatment stage using 5 M NaCl solution. Furthermore, the extraction process for each sample used wet oxidation peroxidation (WPO) with the addition of Fe (II) catalyst. The highest average weight of MPs in the sediment samples was obtained at the 1st sampling point of 2.53% which was dominated by soft fragments. The percentage of MPs weight in the water samples was varied at each sampling point with the highest obtained at the 4th point of 99.2% and was dominated by hard-shaped fragments at all sampling points. The collected aquatic biota was also contaminated by MPs of 68% in fish and 36.40% in shrimp. The types of MPs found in the digestive tract of aquatic biota are in the form of fragments, filaments, films and foam. These results indicate that the aquatic environment of Lake Beratan, Bali has MPs content that varies in sediment, water and aquatic biota which are often consumed by the local community. This must be of particular concern and further investigation, especially regarding the environmental management of the lake area and the relevant authorities in formulating regulations to reduce the harmful effects of MPs contamination.