Sedimentary co-exposure to bis(2-ethylhexyl) phthalate and titanium dioxide nanoparticles aggravate ecotoxicity and ecological risks through disrupted bioenergetics in Caenorhabditis elegans.

Autor: Kuo YH; Department of Bioenvironmental Systems Engineering, National Taiwan University, Taipei 106, Taiwan., How CM; Department of Bioenvironmental Systems Engineering, National Taiwan University, Taipei 106, Taiwan., Liao VH; Department of Bioenvironmental Systems Engineering, National Taiwan University, Taipei 106, Taiwan. Electronic address: vivianliao@ntu.edu.tw.
Jazyk: angličtina
Zdroj: Marine pollution bulletin [Mar Pollut Bull] 2025 Jan 02; Vol. 212, pp. 117515. Date of Electronic Publication: 2025 Jan 02.
DOI: 10.1016/j.marpolbul.2024.117515
Abstrakt: Emerging contaminants in estuarine sediments, such as bis(2-ethylhexyl) phthalate (DEHP) and titanium dioxide nanoparticles (nTiO 2 ), pose ecotoxicological risks that may be exacerbated by co-contamination. This study investigated the impacts of DEHP, nTiO 2 , and their combinations at environmentally relevant concentrations (1, 10, and 100 μg/g) on the soil nematode Caenorhabditis elegans in estuarine-like sediment (14.25‰ salinity). Life history traits and bioenergetics endpoints were examined, with a sample size of ≥ 45 worms or 9 technical repeats per treatment. While individual exposures did not affect growth, the combination of DEHP (1 μg/g) and nTiO 2 (100 μg/g) significantly reduced body length by 19%. Single exposure reduced total offspring by 18-41%, whereas the combination of DEHP and nTiO 2 synergistically worsened reproductive toxicity (52-74% inhibition), as revealed by Loewe's additivity model and Bliss's independence. DEBtox modeling revealed a shift in physiological mode of action from "increased reproductive costs" in singular exposures to "increased growth and reproductive cost" in co-exposure. Moreover, co-exposure significantly intensified the impacts on bioenergetics-related endpoints, including ATP level (single exposure: 33-34%; co-exposure: 56%), mitochondrial damage (single exposure: 15-17%; co-exposure: 40%), and oxidative stress (single exposure: 5-7%; co-exposure: 13%). Risk quotients based on reproductive toxicity EC 10 and DEBtox-derived zb suggested that environmental concentrations of DEHP and nTiO 2 pose high risks in global estuarine sediments, with a 2-fold increase during co-exposure. This study demonstrates that co-contamination of DEHP and nTiO 2 synergistically aggravates ecotoxicities through disrupted energy allocation, highlighting the importance of assessing mixture toxicity in environmental risk assessment of estuarine sediments.
Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(Copyright © 2024 Elsevier Ltd. All rights reserved.)
Databáze: MEDLINE
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