[en] Deep-sea amphipods were trapped at different heights above the sea floor (4500 m depth) during two periods (February and September 1991) in the tropical Atlantic Ocean off Mauritania, and were analysed for their ²¹⁰Po content. In fact, ²¹⁰Po variations were considered an adequate tracer for reflecting changes in trophic inputs at this location. ²¹⁰Po and ²¹⁰Pb concentrations ranged from 23 to 286 Bq.kg^-1 dry weight and from 12 to 67 Bq.kg^-1 dry weight, respectively, when considering the whole organisms with no clear trend with the height of capture above the sea floor. A comparison with ²¹⁰Po concentrations in Eurythenes gryllus and other crustaceans from different locations in the Atlantic was carried out. ²¹⁰Po concentrations in deep-sea amphipods appeared far less important and could be related to their peculiar feeding strategy. A significant inverse correlation was found between ²¹⁰Po concentrations and weight of the amphipods for the two seasons. Allometric equations for ²¹⁰Po concentrations revealed similar slopes for the two periods of sampling; however, ²¹⁰Po concentrations were higher in September compared to February. This difference could be linked to temporal variations both in the mass and organic carbon fluxes into this deep-sea environment. (author)