Polystyrene Nanoparticle Uptake and Deposition in Silkworm and Influence on Growth

This work reports the biological toxicity of nano plastic particles (NPs) to silkworms fed on the bait dopped with polystyrene encapsulated luminescent nanoparticles. The processes of NPs intake and excretion were monitored by means of time-gated optical imaging (TGI) and Inductively Coupled Plasma Mass Spectrometry (ICP-MS), which allowed the quantification of the spatiotemporal deposition of NPs in an individual silkworm. The rates of NPs excretion and sequestration were found to be 99.92% and 0.08%, respectively, and the NPs retentate stayed mainly in the fat body (67.7%), digestive tract (18.0%), and head (7.54%). Adverse effects of NPs exposure were accordingly confirmed such as growth retardation and smaller physique. The results of the present work confirmed the possibility of nano-plastics accumulating and transmitting along the food chain in terrestrial ecosystems. The present work demonstrates the potential of employing silkworm as a model of full metamorphosed insects for exploring the biological impact of NPs on congeneric terrestrial animals, as well as the efficacy of the TGI-MS modality for in situ visualizing and quantifying the propagation of NPs via the primary food chain.