Responses to iron oxide and zinc oxide nanoparticles in echinoderm embryos and microalgae: uptake, growth, morphology, and transcriptomic analysis

Abstract

We investigated the toxicity of Iron oxide and Zinc oxide engineered nanoparticles (ENPs) on Paracentrotus lividus sea urchin embryos and three species of microalgae. Morphological responses, internalization, and potential impacts of Fe₂O₃ and ZnO ENPs on physiology and metabolism were assessed. Both types of ENPs affected P. lividus larval development, but ZnO ENPs had a much stronger effect. While growth of the alga Micromonas commoda was severely impaired by both ENPs, Ostreococcus tauri or Nannochloris sp. were unaffected. Transmission electron microscopy showed the internalization of ENPs in sea urchin embryonic cells while only nanoparticle interaction with external membranes was evidenced in microalgae, suggesting that marine organisms react in diverse ways to ENPs. Transcriptome-wide analysis in P. lividus and M. commoda showed that many different physiological pathways were affected, some of which were common to both species, giving insights about the mechanisms underpinning toxic responses.

Keywords:

• Nanoparticles
• toxicity
• marine organisms
• metal oxide
• transcriptomics

Disclosure statement

The authors declare that there is no conflict of interest regarding the publication of this article.

The authors thank the CNRS (Missions pour les initiatives transverses et interdisciplinaires) and EMBRC. France for financial support.

Acknowledgments

The authors would like to dedicate this publication to Dr. Hervé Moreau who died unexpectedly during the revision of this article.

The authors thank Dr Pascal Giraud and the ORDECO organization (https://www.ordeco.org/) for fruitful discussions and assistance during the project, Christophe Salmeron (SU/CNRS BioPIC Imaging and OOB Cytometry platform) for cytometry analysis, Elodie Desgranges (OOB-UMR7232) for technical assistance in microalgae culture and the microscopy platform of the Institut des Matériaux de Paris Centre (IMPC) - Fédération de Recherche 2482.

Correction Statement

This article has been republished with minor changes. These changes do not impact the academic content of the article.