Abundance and distribution of marine litter on the beaches of Okinawa Island, Japan

• Published in: Marine pollution bulletin 2024-03, Vol.200, p.116036-116036, Article 116036
• Main Authors: Ilechukwu, Ifenna, Das, Rocktim Ramen, Jamodiong, Emmeline A., Borghi, Stefano, Manzano, Geminne G., Hakim, Agus Alim, Reimer, James Davis
• Format: Article
• Language: English
• Subjects: Bathing Beaches; Cigarette butts; Clean coast index (CCI); Environmental Monitoring; Japan; Marine debris; Plastic bottle caps; Plastics - analysis; Pollution; Single-use plastics; Waste Products - analysis
• ISSN: 0025-326X; 1879-3363
• DOI: 10.1016/j.marpolbul.2024.116036

This study evaluated the distribution and abundance of marine litter on 30 beaches around Okinawa Island, Japan. Beach quality indices and multivariate statistical analyses were used to assess the quality of the beaches and their pollution patterns. A total of 11,626 items weighing 513.49 kg with an average density of 0.13 ± 0.10 items/m2 were collected. Litter was dominated by plastics (81.72 %), broken glass (8.38 %), and cigarette butts (7.44 %), and 74.05 % of total litter was from land-based sources. Single-use plastics (SUPs) were present in all surveyed beaches and made up 30.54 % of the total litter. The clean coast index (CCI), plastic abundance index (PAI), and hazardous index (HI) were between 0.1 and 7.6, 0.1–4.0 and 0.01–1.42, respectively, indicating low to moderate levels of pollution of Okinawan beaches. This study should aid in the formation of strategies to deal with marine litter in Okinawa, other areas of Japan and the Asia-Pacific region. [Display omitted] •First report of marine litter survey on Okinawa Island beaches.•On the 30 beaches surveyed, 11,626 items weighing 513.49 kg were found.•74.05 % of the litter were from land-based sources.•Plastics constituted 81.72 % of the marine litter.•Average litter density was 0.13 ± 0.10 items/m2.