Differential Gene Expression in Daphnia magna Suggests Distinct Modes of Action and Bioavailability for ZnO Nanoparticles and Zn Ions

Citations Over TimeTop 10% of 2010 papers

Abstract

Zinc oxide nanoparticles (ZnO NPs) are being rapidly developed for use in consumer products, wastewater treatment, and chemotherapy providing several possible routes for ZnO NP exposure to humans and aquatic organisms. Recent studies have shown that ZnO NPs undergo rapid dissolution to Zn(2+), but the relative contribution of Zn(2+) to ZnO NP bioavailability and toxicity is not clear. We show that a fraction of the ZnO NPs in suspension dissolves, and this fraction cannot account for the toxicity of the ZnO NP suspensions to Daphnia magna. Gene expression profiling of D. magna exposed to ZnO NPs or ZnSO(4) at sublethal concentrations revealed distinct modes of toxicity. There was also little overlap in gene expression between ZnO NPs and SiO(x) NPs, suggesting specificity for the ZnO NP expression profile. ZnO NPs effected expression of genes involved in cytoskeletal transport, cellular respiration, and reproduction. A specific pattern of differential expression of three biomarker genes including a multicystatin, ferritin, and C1q containing gene were confirmed for ZnO NP exposure and provide a suite of biomarkers for identifying environmental exposure to ZnO NPs and differentiating between NP and ionic exposure.

Related Papers

• → Toxicity and bioaccumulation of TiO2 nanoparticle aggregates in Daphnia magna(2009)522 cited
• → The critical importance of defined media conditions in Daphnia magna nanotoxicity studies(2013)46 cited
• → Effects of water hardness and humic acid on zinc toxicity to Daphnia magna Straus(1988)74 cited
• → Toxicity of dodecylbenzene to algae, crustacean, and fish – Passive dosing of highly hydrophobic liquids at the solubility limit(2020)11 cited
• → The Ecotoxicity of Nanoparticles Co2O3 and Fe2O3 on Daphnia magna in Freshwater(2021)4 cited