Rare earth elements (REE) are a group that includes lanthanides, yttrium (Y) and scandium (Sc). REE are essential for the development of modern technologies, being widely used in clean technologies, electronic devices, medicine, agriculture and livestock. The demand for REE is likely to increase over the next 25 years due to its increasing use in decarbonization technologies. The main natural source of REE for the environment is the weathering of the continental crust. Nonetheless, as its use increases, its release into the environment due to anthropogenic activities also increases. Recent research demonstrates that anthropogenic input is changing the natural abundance of REE in the environment. However, there is a lack of studies on the fate, bioaccumulation, toxicity and dynamics of REE in food webs, making it difficult to estimate potential human and ecological risks. In this work we collected abiotic and biotic components in an impacted estuarine system to evaluate the trophic transfer and fate of REE. REE were quantified in sediments, suspended particulate matter (SPM) and in organisms from different trophic levels. The highest ΣREE concentrations were found in sediments (180 ± 4.24 mg kg-1) and SPM (163 ± 12.6 mg kg-1). Phytoplankton (45.7 ± 5.31 mg kg-1), periphyton (51.6 ± 1.81 mg kg−1) and zooplankton (68.5 ± 1.27 mg kg−1) are the main sources of exposure and transfer of REE to the food web. ΣREE concentrations were several orders of magnitude lower in bivalves, crustaceans and fish (6.01 ± 0.11 mg kg−1, 1.22 ± 0.18 mg kg−1 and 0.059 ± 0.003 mg kg−1, respectively) than in plankton. The ΣREE concentration decreased as a function of trophic position, indicating that REE are susceptible to trophic dilution. Our study suggests that seafood consumption is unlikely to be an important source of REE for humans. However, given the numerous sources of dietary introduction of REE, they must be monitored for a possible harmful cumulative effect. This study provides important new information about REE concentrations, patterns, and trophic transfer.