Cellulose Acetate Nanoparticles: Impacts of Concentration and Time of Exposure on the Biochemistry and Hematology of Juvenile Colossoma Macropomum

This study evaluated the physiological impacts of the exposure of Colossoma macropomum to different concentrations of cellulose acetate nanoparticles for different amounts of time. A total of 120 juvenile C. macropomum (38.91 ± 5.57 g and 13.76 ± 0.74 cm in total length) were distributed in 12 tanks of 150 L, in a recirculating aquaculture system (RAS). The juveniles were kept in water containing cellulose acetate nanoparticles (CANs) at four different concentrations (treatments): 0 mg L⁻¹, 0.01 mg L⁻¹, 0.10 mg L⁻¹ and 1.00 mg L⁻¹. Blood samples were collected after 1 and 24 hours of exposure. The juveniles were then relocated to a tank with clean water, where they remained for another 24 hours, at which point a new blood sample was collected (24hR). Hemoglobin, serum protein and globulin were reduced after 1h of exposure for the group exposed to 1.00 mg L⁻¹ of CANs. Glucose levels increased after 24h for the groups exposed to 0.10 and 1.00 mg L⁻¹. Urea increased after 1h for the groups exposed to 0.10 and 1.00 mg L⁻¹. Triglycerides and cholesterol were reduced both after 1h and 24h of exposure for the 1.00 mg L⁻¹ group, returning to baseline levels at 24hR. The activities of aspartate aminotransferase (AST) and alanine aminotransferase were altered after 24h. Albumin was lower after 1h and 24h compared to after 24hR for the 1.00 mg L⁻¹ group. Exposure of juvenile C. macropomum to CANs caused transient physiological changes, with partial recovery being observed after transfer to clean water.