Comparative sub-chronic toxicity of potato peel starch-based bioplastic and low-density polyethylene in mice: Hematological, biochemical, inflammatory, and histomorphological assessment

The increase in plastic pollution has raised serious concerns regarding the biological toxicity of conventional synthetic and emerging bio-based plastics; however, the evidence regarding their in vivo toxicity is limited. This study explored the dose-dependent systemic toxicity of prepared potato peel-derived starch-based bioplastic and low-density polyethylene, compared to a control group, using manually ground particles of different sizes, with the PSBP exhibiting an average hydrodynamic size of 681.95 nm. The study included 42 male Swiss albino mice (n = 6 per group), which were administered 50, 150, or 250 mg/kg of the doses through an intragastric gavage tube, three times weekly for 12 consecutive weeks. The toxicity was assessed using data from hematological profiling, hepatic and renal markers, electrolyte homeostasis, inflammatory cytokines, histology, and confocal imaging of organs, such as the liver, kidney, and heart. The extent of toxicity was much greater in the LDPE groups than in the PSBP groups, compared to the control. For instance, the value of TNF-α increased rapidly from 15 ± 3 pg/mL in the control group to 26 ± 5.4 pg/mL and 60 ± 7 pg/mL in the PSBP-H and LDPE-H groups, respectively. These parameters were supported by an evident elevation in inflammatory cytokines and clear damage in the qualitative histomorphology of vital organs. These findings provide evidence that higher doses of starch-based bioplastics can induce biological toxicity, but their effect appears lower than that of conventional polyethylene under the present experimental conditions.