{
  "abstract": "The increasing production of nanomaterials has raised concerns regarding their environmental presence and potential adverse effects on non-target aquatic species. This study investigated the physiological impacts of acute (24 h) exposure of Oreochromis niloticus to copper oxide nanoparticles (CuO-NPs) of two distinct morphologies: nanorods (NRs) and nanospheres (NSs). Nanoparticles were synthesized and characterized via transmission electron microscopy, revealing significant differences in size, shape, and colloidal stability. Juvenile tilapia was exposed to concentrations ranging from 50 to 800 µg/L to evaluate routine metabolism (specific oxygen consumption), ammonia excretion, and swimming performance to fatigue. Both NRs and NSs significantly altered physiological parameters with distinct patterns. Oxygen consumption increased dose-dependently, reaching a 51% elevation with NRs (400 µg/L) and up to 254% with NSs (800 µg/L). Ammonia excretion was significantly inhibited in groups exposed to NRs. At 200 µg/L, excretion was nearly three times lower than in the control group, suggesting disturbances in gill function. In contrast, NSs induced significant increases in ammonia excretion (up to 127% at 800 µg/L), likely associated with enhanced protein catabolism. Swimming performance was also severely impaired, with NRs causing up to a 55% reduction in time to fatigue (200 µg/L), indicating locomotor and neuromuscular compromise. Comparative analysis showed that nanorods were consistently more toxic, supporting the “Trojan horse” hypothesis, likely due to their higher aggregation tendency and consequent release of CU2+ ions. These findings underscore the critical role of morphology, colloidal stability, and solubility in the ecotoxicological assessment of nanomaterials. We conclude that CuO-NPs, particularly in the form of nanorods, pose a significant risk to fish physiology and locomotor performance, reinforcing the need to integrate morphological, physiological, and behavioral endpoints in environmental risk assessment and regulatory policies for the safe use of these nanomaterials.\n\nGraphical abstract:",
  "abstract_shown": true,
  "affiliations": [
    "Instituto de Pesca-APTA-Governo Do Estado de São Paulo, Cananeia, SP Brazil",
    "Development and Innovation Laboratory, Butantan Institute, São Paulo, SP Brazil",
    "Laboratório Nacional de Nanotecnologia (LNNano), Centro Nacional de Pesquisa Em Energia E Materiais (CNPEM), Campinas, SP Brazil",
    "Centro de Estudos Do Ambiente E Do Mar (CESAM), Universidade de Aveiro, Aveiro, Portugal",
    "Departamento de Biologia, Universidade de Aveiro, Aveiro, Portugal"
  ],
  "article_type": "research article",
  "arxiv": null,
  "author_total": 5,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Edison Barbieri"
    },
    {
      "affs": [
        0
      ],
      "name": "Fabíola Sant’Ana Oliveira"
    },
    {
      "affs": [
        1
      ],
      "name": "Luiz Gustavo Ribeiro"
    },
    {
      "affs": [
        2
      ],
      "name": "Luelc Souza da Costa"
    },
    {
      "affs": [
        3,
        4
      ],
      "name": "Bruno Nunes"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/2xh9k62jzhh3c.bib",
  "cited_by": 0,
  "doi": "10.1007/s10695-026-01821-x",
  "fulltext_url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC13714000/",
  "id": "2xh9k62jzhh3c",
  "issns": [
    "0920-1742",
    "1573-5168"
  ],
  "landing_url": "https://doi.org/10.1007/s10695-026-01821-x",
  "language": "en",
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "heading",
      "Research"
    ],
    [
      "openalex",
      "2307|Environmental Toxicology and Ecotoxicology"
    ]
  ],
  "openalex": "W7223968011",
  "pdf_url": null,
  "pmcid": "PMC13714000",
  "pmid": "42944982",
  "published": "2026-10-27",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/2xh9k62jzhh3c.ris",
  "sources": [
    {
      "first_seen": "2026-11-01T12:21:34Z",
      "native_id": "PMC13714000",
      "source": "pmc",
      "url": "https://doi.org/10.1007/s10695-026-01821-x"
    }
  ],
  "subjects": [
    {
      "field": "medicine",
      "origin": "openalex:2307|Environmental Toxicology and Ecotoxicology",
      "subfield": "pharmacology-toxicology"
    }
  ],
  "title": "Comparative effects of copper oxide nanoparticle morphology (nanorods vs. nanospheres) on the metabolism and swimming performance of Oreochromis niloticus",
  "title_text": "Comparative effects of copper oxide nanoparticle morphology (nanorods vs. nanospheres) on the metabolism and swimming performance of Oreochromis niloticus",
  "type": "peer-reviewed",
  "updated_at": "2026-11-01T12:21:34Z",
  "url": "https://research.draconitic.com/paper/2xh9k62jzhh3c",
  "venue": "Fish Physiology and Biochemistry",
  "versions": []
}