The influx of international debris, especially plastic, has emerged as a significant environmental challenge for coastal ecosystems. Our study on Cozumel Island (Mexico) investigated the origin and distribution of plastic debris across nine beaches, considering factors such as wind patterns and ocean currents. Results revealed that over 90% of the waste, for which provenance could be confirmed, originated from outside the island, reflecting the global nature of marine pollution. High densities of plastic debris were found on windward beaches, with waste originating from at least 25 countries. This study underscores the pressing need for international cooperation and sustainable waste management strategies to mitigate the environmental impact of marine debris on Cozumel and similar regions. Effective policies combining ecological preservation and sustainable tourism are crucial for addressing the international issue of plastic pollution and safeguarding coastal ecosystems worldwide.