ABSTRACT
The rapid advancement of technological infrastructure has hastened the progression of nanoscience and fostered the widespread application of nanoparticles across various domains. Nevertheless, the unintended release of nanoparticles into the environment carries potential hazards. Despite numerous efforts to evaluate their potential risks, our knowledge of their environmental impact, particularly on vital elements of aquatic biodiversity like fish, remains limited. This study delved into the harmful effects of aluminum oxide nanoparticles (Al2O3 NPs) on the hatching rate and survival of Clarias gariepinus embryos and larvae. The embryos (3 hours post-fertilization) were subjected to varying concentrations (0, 0.5, 1, 5, and 10 mg/l) of Al2O3 NPs for 48 hours. As the concentration of Al2O3NPs increased and the exposure duration extended, both hatching and survival rates were adversely affected. This trend was most pronounced at 48 hours post-fertilization, where the order of hatched embryos was control = 0.5 mg/l > 1 mg/l > 5 mg/l > 10 mg/l. At 24 hours post-fertilization, the percentage of hatchability was 16.7%, 13.3%, 3.3%, 11.7%, and 13.3% for the control, 0.5 mg/l, 1 mg/l, 5 mg/l, and 10 mg/l treatment groups, respectively. At 36 hours post-fertilization, the percentage of hatchability was 33.3%, 18.3%, 6.7%, 18.3%, and 15% for the control, 0.5 mg/l, 1 mg/l, 5 mg/l, and 10 mg/l treatment groups, respectively. By 48 hours post-fertilization, the percentage of hatchability was 100%, 100%, 91.7%, 71.7%, and 63.3% for the control, 0.5 mg/l, 1 mg/l, 5 mg/l, and 10 mg/l treatment groups, respectively. In terms of mortality, the order was control < 0.5 mg/l < 1 mg/l < 5 mg/l < 10 mg/l, with this trend being most pronounced at 48 hours post-fertilization. At 24 hours post-fertilization, mortality was 0% across all treatment groups. At 36 hours postfertilization, mortality rates were 0%, 0%, 1.7%, 1.7%, and 1.7% for the control, 0.5 mg/l, 1 mg/l, 5 mg/l, and 10 mg/l treatment groups, respectively. By 48 hours post-fertilization, mortality rates were 0%, 1.7%, 6.7%, 8.3%, and 13.3% for the control, 0.5 mg/l, 1 mg/l, 5 mg/l, and 10 mg/l treatment groups, respectively. These findings underscore the imperative for further research aimed at comprehending the underlying mechanisms and evaluating the long-term ecological consequences of nanoparticle contamination in aquatic ecosystems. Gaining insight into the potential risks linked to nanoparticles is crucial for informed decision-making in industries that employ these materials and for the formulation of effective environmental management strategies.
