Post-Harvest Chemical and Probiotic Interventions in Amazonian Fisheries: An Exploratory Evaluation of Trace Element Dynamics

Trace element contamination in Amazonian freshwater ecosystems threatens riverine food security. This study evaluated two post-harvest treatments—ethylenediaminetetraacetic acid (EDTA) and Lactobacillus fermentum—to assess cadmium (Cd) and lead (Pb) variations in edible muscle of four Amazonian fish species (Cichla monoculus, Pimelodus jivaro, Platynematichthys notatus, and Serrasalmus rhombeus). Concentrations were determined using ICP-OES. Platynematichthys notatus exhibited the highest baseline bioaccumulation, whereas C. monoculus showed the lowest. Although main treatment effects should be considered exploratory, distinct species-dependent trends emerged. EDTA achieved the highest Cd reduction in P. notatus (49.78%), while L. fermentum demonstrated notable Cd and Pb reductions in C. monoculus, P. notatus, and S. rhombeus. Conversely, relative concentration increases occurred in P. jivaro under both treatments, reflecting matrix-related effects. These findings suggest that post-harvest efficiency depends on fish species and metal type. Probiotic post-harvest processing represents a promising strategy for reducing dietary exposure to Cd and Pb in Amazonian fisheries, though optimizing operational parameters for community-level applications remains necessary.