ABUNDANCE AND CHARACTERISTICS OF MICROPLASTICS IN THE UMEDA RIVER, TOYOHASHI, JAPAN

Abstract

The plastic debris can be broken down into smaller fragments called macroplastic, microplastic (MP), and nanoplastic due to exposure to solar radiation, mechanical, and biological forces. Microplastics are generally defined as plastic particles that have a size smaller than the specified upper size limit of 5 mm. Microplastics with characteristics such as large porosity, high surface area, and various surface functions, are very susceptible to absorbing toxic contaminants from aquatic systems. Therefore, it is necessary to conduct research related to the presence of microplastics in waters that will be consumed by humans. Especially on the Umeda river that flows through the city of Toyohashi, Japan. The area around the Umeda River is one of the major agricultural areas in Japan. Therefore, it is possible that there will be a lot of plastic waste that can pollute the Umeda River. This study analyzed the abundance of microplastics, as well as their characteristics in the form of shape, color, type, and size in the Umeda River in Aichi Prefecture, Japan. Sampling collection was carried out with a cone-shaped plankton net which had a length of 75 cm, a diameter of 30 cm, and a pore size of 0.3 mm with a collecting bag or cod end diameter of 4 cm, three pieces. Sample preparation and extraction were carried out in accordance with the River Microplastic Survey Guidelines written by the Environment Division, Water and Air Environment Bureau, Ministry of the Environment of Japan. Potential microplastic particles were then identified and characterized based on shape, size, and color. The average abundance of microplastics found in all of the sampling point was 1.7 particles/m3.