Toxicity evaluation of polypropylene microplastic on marine microcrustacean Artemia salina: An analysis of implications and vulnerability

Polypropylene microplastic particles are one of the predominant pollutants in marine ecosystems and their toxic effects are unknown in aquatic biota. The study aims to prepare the spherical shaped polypropylene microplastics (size range 11.86 μm-44.62 μm) and assess their toxic effects (1, 25, 50, 75 and 100 μg/mL) in various life stages (nauplii, metanauplii and juvenile) of marine microcrustacean Artemia salina within 48 h. In addition, microplastics ingestion by Artemia nauplii was proved by FTIR analysis. The results revealed, microplastics accumulation in their tract leads to change in their homeostasis, as followed increase in the oxidative burst causes mortality in nauplii (LC₅₀ 40.947 μg/mL) and meta nauplii (LC₅₀ 51.954 μg/mL). In juvenile, swimming behaviour was changed. Moreover, microplastic consumption disturbs the antioxidant biomarkers such as superoxide dismutase (SOD), catalase (CAT), reduced glutathione (GSH), glutathione -S- Transferase (GST) and reduces the neurotransmitter enzyme acetylcholinesterase (AChE) activity. In addition, histology of juvenile Artemia showed damage in epithelial cells. This study indicates that exposure to polypropylene microplastics is more harmful to zooplanktonic organisms of the marine ecosystem.