A FIELD INVESTIGATE ON CURENT STATUS OF MICROPLASTIC POLLUTION ON SANDY BEACHES OF OSAKA BAY, JAPAN

Abstract

 There is worldwide concern about the impact of microplastics on marine ecosystems, surveys of the state of pollution in oceans and rivers are being conducted. In this study, we conducted a sampling survey of 13 sandy beaches in Osaka Bay to understand the contamination status of an inner coastal bay located between rivers and the ocean. Microplastics were distributed at several locations from the shoreline to coastline, and most tended to be deposited at elevations higher than the highest monthly tide level. The amount of microplastics deposited varied from 50 to 9,500 pieces/m², and the maximum difference was about 100 times. The results of the microplastic deposition rate for each coast considering the distribution condition showed that the average value for the beaches of Osaka Bay was 52.0 microplastics/m², whereas the value for the beaches at inner part of the bay area was 253.0-312.6 microplastics/m², indicating a high degree of contamination.