Comparative assessment of alumina-based nanomateriales in two aquatic autochthonous species, Cnesterodon decemmaculatus (Pisces: Poeciliidae) and Rhinella arenarum larvae (Amphibia: Bufonidae).

CRISTINA PÉREZ-COLL; GABRIELA SVARTZ; SOLEDAD PÉREZ CATÁN

Cartagena

Congreso; Setac Latin America 13th Biennial Meeting; 2019

SETAC LA

Alumina nanoparticles (NP-Al2O3) are widely used as coatings and abrasives due to their excellent dielectric and abrasive properties. Nevertheless one of the most important applications at local level is the synthesis of ceramics with nano porous composite membranes and catalysts, eg Ni/gamma alumina for ultrafiltration processes. These materials have a high adsorption capacity and are considered chemically active due to the presence of oxhydryl radicals. Due to these characteristics and considering that these NPs may appear in water body receptors as effluent discharges make them potentially dangerous, which deserve a more rigorous evaluation of their effects on the environment and human health. The aim of this study was to comparatively evaluate the acute and chronic toxicity of a nanoceramic catalyst Ni/γ- Al2O3 (NC) and NPs involved in their synthesis: γ- Al2O3 support (SPC) and NiO/γ- Al2O3 precursor (PC) on two aquatic species, Cnesterodon decemmaculatus adults and Rhinella arenarum larvae by standardized bioassays. Amphibian larvae were more sensitive to NPs than fish. In this sense, toxicity significantly increased over time in R. arenarum larvae exposed to PC and NC and remained almost constant to SPC. PC toxicity was greater than that of NC and SPC at chronic exposure. The values of 96 h-LC50 were 72.05, 91.23 and 109.93 mg/L and 336 h-LC50 were 70, 5.11 and 18.47 mg/L for SPC, PC and NC respectively. Amphibian larvae also exhibited sublethal effects such as collapsed cavities, edema, axial flexures, and behavioural alterations as hyperkinesia and reduced movements. In contrast, exposed Cnesterodon decemmaculatus organisms survived to NP highest concentration (100 mg/L) even without exhibiting sublethal effects. These results evidence the need to develop standardized ecotoxicity bioassays with specific sensitive species and to perform more than one species test in order to ensure environmental sustainability and for species conservation purposes.