POLYSTYRENE MICROBEADS RELEASE VOLATILE COMPOUNDS: EFFECT ON ARTEMIA SALINA EARLY DEVELOPMENT

Polystyrene is one of the most diffused contaminants worldwide. Once released in the environment, it degrades into micro and nanofragments that severely impact vegetal and animal organisms. A plethora of toxic effects have been reported on different organs and tissues2. In the present work, we examined the effects of 3 μm polystyrene beads MP on the early development of the model species Artemia salina. The first objective was to assess whether beads release volatile compounds1 (VOCs) in culture seawater. Then, the effects of beads/VOCs were determined at the level of oxidative stress1 and morphofunctional damage, in nauplii obtained from intact and dechorionated cysts2. Results demonstrated that MP releases significant amounts of ethylbenzene, xylene, benzaldehyde, and styrene, at concentrations that may result in cytotoxicity and genotoxicity. Nauplii exposed to MP/VOCs showed reduced hatching and delayed development, probably due to the significant oxidative stress that occurred during embryogenesis. Significant damage was observed at the level of the gut brush border, as indicated by the reduced presence of glcNAc while yolk was poor in galNAc, and its resorption was markedly delayed. The effects of MB ingestion were also determined and excluded in specific experiments in which the nauplii were exposed to beads after hatching. In conclusion, two important pieces of evidence emerge: polystyrene toxicity in early nauplii is due to the release of chemicals, and second, the yolk platelets must be added among targets. If confirmed, these results indicate that microplastic toxicity mechanisms should be reconsidered.