Background The Thondi coast is rich in valuable natural marine resources and socio-economically significant activities like agriculture, aquaculture, and fishing. The area receives an excess of untreated solid and liquid waste as a result of these activities. The study focuses on the abundance, distribution, and status of the Clean-Coast Index (CCI) of marine debris from the Thondi coast, Palk Bay, Southeast coast of India. This is the first research work focused on assessing the type and quantity of marine debris on the Thondi coast. Results A total of 1636 marine debris items/m2 and their 4.09 concentration of the items/m2 were determined in the marine debris: plastics (77.49%), cotton swabs (8.62%), cigarette butts (10.15%), and food containers (3.73%). From the result, the CCI had ranged between 4.25 (clean) and 20.4 (extremely dirty) with a mean of 8.92 (moderate) in the Thondi coast assessed. Conclusion This study was conducted for the first time in this region. Finally, the high CCI value of 20.4 on the coast indicated that the marine debris pollution levels were high at the time of sampling in the middle part of the Thondi coast (most of the beaches are covered with plastic) due to land-based marine debris (62.45%), sea-originated marine debris (21.14%), and unknown sources (16.41%) of the items. Our findings served as a baseline for potential evaluations of the marine environment. Input prevention should be the goal of management efforts, including proper waste management, plastic recycling, and stringent penalties for illegal waste dumping.

Background: The Thondi coast is a rich source of valuable natural marine resources, as well as many socioeconomically significant activities like agriculture, aquaculture, and fishing. The area receives an excess of untreated solid and liquid waste as a result of these activities. The study focus on the abundance, distribution, and status of the Clean - Coast Index (CCI) of marine debris from the Thondi coast, Palk Bay, Southeast coast of India. This research was the first to assess the type and quantity of marine debris on the Thondi coast. Results: A total of 1636 marine debris items/m2 and 4.09 density of the items/m2 were determined in the marine debris: plastics (77.49%), cotton swabs (8.62%), cigarette butts (10.15%), and food containers (3.73%). From the result, the CCI is ranged between 4.25 (clean) and 20.4 (extremely dirty) with a mean of 8.92 (moderate) in the Thondi coast assessed. Conclusion: These studies were conducted for the first time in this region. Finally, the high CCI value of 20.4 in the coast indicates that the marine debris pollution levels are high at the time of sampling in the middle part of the Thondi coast (most of the beach is covered with plastic) due to land – based marine debris (62.45%), sea – originated marine debris (21.14%) and unknown sources (16.41%) of the items. Our findings serve as a baseline for potential evaluations of marine environments. Input prevention should be the goal of management efforts, which include proper waste management, plastic recycling, and stringent penalties for illegal waste dumping.