Toxicity assessment of bioplastics on brine shrimp (Artemia franciscana) and cell lines

Abstract

Polylactic acid (PLA) and polybutylene succinate (PBS), are categorized as biodegradable bioplastics that have progressively being utilized as food packaging replacing the obtrusive petroleum plastic. This study aims to evaluate the toxicity of bioplastics and petroleum-based plastic polyethylene (PE) on Artemia franciscana and animal cell lines. Each plastic sample was assessed in its powdered form, and the size distribution of PE, PLA, and PBS microplastic particles was observed by optical microscopy. Additionally, the toxicity of hatching percentage and mortality rate was investigated. The results demonstrated that the percentage of hatching and the mortality rate post treatment with PLA and PBS particles for 24 and 48 h did not significantly alter in comparison to those treated with PE particles. However, the percentage of Artemia hatching reduced post treatment with plastic particles in comparison to the control, as well as the mortality rate increased with a high concentration of plastic particles. The morphology of Artemia after ingesting microplastic particles was obtained using phase contrast inverted microscopy. The accumulation of plastic in the Artemia gut was observed succeeding its exposure to PE, PLA, and PBS particles. In addition, the cytotoxicity of plastics on human keratinocyte (HaCaT), normal human dermal fibroblast (NHDF), and African green monkey kidney (Vero) cell lines were determined by MTT assay. The result exhibited that increasing concentrations of microplastic particles had substantially less toxic to practically nontoxic effect on the cells. The biomolecule profile by synchrotron-IR technique displayed that plastics potentially have more alteration effect in epithelial kidney cells (Vero) than fibroblasts (NHDF) and keratinocytes (HaCaT). Our results demonstrate that PE, PLA, and PBS had toxicity on Artemia following ingestion, in accordance with the concentration and duration tests. Moreover, microplastic particles were nontoxic or harmless to animal cell lines and altered some intracellular biomolecule profiles. These discoveries are essential not only for environmental health risk assessment but also in order to establish recommendations toward safer utilization of bioplastics-based materials for a robust lifestyle.