In a forthcoming publication (Bahers, Tanguy, and Pincetl 2020), we have shown that port cities are particularly interesting territories for studying urban metabolism. Transited through these port cities, flows of goods and energy are very important that cross the oceans to the regions concerned, causing a chain of pollution that extends local emissions through distribution and consumption, but also through ocean pollution related to transportation. This continuum of pollution is poorly identified, measured and analyzed by environmental assessment tools, by actors in the economic sectors and by territorial and international policies. Towards the new field of research of “politico-industrial ecology” (Pincetl et Newell 2017) that provides a framework to track the quantities of resource flows across space and time and to study social and environmental dynamics that reveal indirect flows of imports, we will discuss the dependency on a distant hinterland and the metabolic inequalities. The methodological question remains: how to couple the "flow" approaches from environmental engineering, and the "territory" approaches from social geography and political ecology? It would make it possible to decipher intertwined social and environmental dynamics and to combine the modeling of the circulation of flows and the political and societal perspective. The metabolism of the port cities of Nantes-Saint-Nazaire (France) and Gothenburg (in Sweden) will be compared to explore this issue.