Egeria densa remediates the aquatic environment and reduces 14 C-deltamethrin bioaccumulation in Danio rerio .

Deltamethrin is an insecticide with high toxicity to non-target aquatic organisms. Environment-friendly alternatives to removing insecticides from water bodies, like phytoremediation, require species to uptake and/or dissipate pesticides from water. Our research investigated the ability of Egeria densa plants to absorb and dissipate 14 C-deltamethrin from water, and bioaccumulation in Danio rerio . The variables were four densities of E. densa (0, 234, 337, and 468 g dry weight m -3 ), in tanks with seven adults of D. rerio , with three replicates. Dissipation was evaluated at 0, 24, 48, 72, and 96 h after application (HAA). After 96 HAA, the uptake of 14 C-deltamethrin by plants and accumulation in fish were assessed. The E. densa increased 14 C-deltamethrin dissipation and reduced bioaccumulation in zebrafish. The DT 50 decreased 3-fold in treatments with 337 and 468 g m -3 of E. densa . The plants absorbed 32% of the 14 C-deltamethrin applied, regardless of plant density. The bioaccumulation in fish was 8.21% without E. densa and only 1% in treatments with 468 g m -3 of plants. These results suggest phytoremediation using E. densa is a possible alternative to removing deltamethrin from water and reducing the accumulation in non-target organisms, reducing the environmental impact of insecticides in aquatic ecosystems.