Global plastic production is emblematic of the Anthropocene with an exponential and endless growth of 4% per year, reaching around 400 million metric tons in 2022. Plastics are everywhere, in every economic sector and under many chemical and physical configurations. They are widely used for 50 years, persistent in the environment and are not biodegradable, that is why they are found in soils, water, air and biota as macro- (> 5 mm), micro- (1 µm <> 5 mm), or even nanoplastics (< 1 µm). Consequently, the endless production growth yields an endless leakage into the environment. In contrast with other persistent chemical pollutants gathered within the term “novel entities”, plastics – especially macroplastics – are visible. They thus focalize the public’s attention thanks to impressive images and/or biased representations from polluted oceans and rivers. Rivers are major pathways of plastics from lands into the Ocean. However, there is still a huge lack of knowledge on how much and how riverine litter, including macroplastics, is transferred into the Ocean. Quantitative measurements of macroplastic emissions in rivers even suggest that a small fraction (0.001 to 3%) of the Mismanaged Plastic Waste generated within a river basin finally reaches the sea. Macroplastics may remain within the catchment and on coastlines because of complex transport dynamics that delay the transfer of plastic debris. In order to better understand those dynamics, we performed tracking of riverine litter over time. First, hundreds of date-prints items were collected on riverbanks in the Seine estuary. The distribution of their Use-By-Dates suggests that riverine litter may remain stored on riverbanks for decades. Second, we performed real time tracking of floating and sub-floating bottles using GPS-trackers in the estuary covering a wide range of hydrometeorological conditions and tidal cycles. Results show a succession of storage/remobilization episodes in combination with back and forth transport in the estuary related to tides. Plastic debris are thus submitted to an endless journey from rivers to the Ocean during which endless fragmentation occurs from macro- to micro- and perhaps nanoplastics well before they reach the Ocean. Due to this chaotic transport from land to sea, the residence time of these debris is much longer than the transit time of water. This offers the opportunity to collect them before they get fragmented and/or reach the Sea. To prevent endless cleaning of plastic debris, “a historic resolution was adopted to develop an international legally binding instrument on plastic pollution” in order to tackle plastic pollution at source. But time is running out because an endless world is not compatible with a finite world, where six on nine of the identified planet boundaries, including “novel entities”, have already been exceeded.