The potential ameliorative role of Dimercaptosuccinic acid against the toxicity of Titanium Dioxide Nanoparticles on Caelatura nilotica clams.

The prevalent use of nanoparticles has adverse negative effects on biosystems. Subsequently, this study aimed to use Caelatura nilotica to assess the ecotoxicity of TiO₂ NPs and how Dimercaptosuccinic acid (DMSA) improves these effects. Two concentrations of TiO₂ NPs (25 and 150 µg/L) were used for 28 days. TiO₂ NPs bioaccumulation, gonadal weight, gonado-somatic index, and histopathological alterations of gonads were determined. The tissues' accumulation of TiO2 NPs was concentration-time-dependent: it was 78.5 ± 28.93 μg/g dry weight in the exposed clams to 150 µg/L TiO₂ NPs after 4 weeks of exposure. The gonadal weight and gonado-somatic index significantly decreased of the exposed group to 150 µg/L TiO₂ NPs over the experimental period that they ended with values (1.01 ± 0.57 gm, 19.15 ± 7.75%, respectively). There are some histological alterations in the gonads of C. nilotica such as necrosis, deteriorated connective tissue, increased fibrous tissue, a reduced presence of mature sperms and mature ova, and irregular shapes of testicular/ovarian follicles. When using Dimercaptosuccinic acid (DMSA), this led to a reduction in accumulation of TiO₂ NPs by the end of the experiment. So, C. nilotica is a promising model to reflect the adverse nano-toxics. DMSA emerges as a potentially valuable chelating agent that abolishes the negative effects of these nanoparticles.