Toxicity of TiO ₂, SiO ₂, ZnO, CuO, Au and Ag engineered nanoparticles on hatching and early nauplii of Artemia sp.

Abstract

The potential of environmental release enhances with increased commercial applications of the nanomaterials. In this work, a simple and efficient test to estimate the acute toxicity of nanoparticles is carried out on Artemia species and their hatching rates. We have tested six different engineered nanoparticles (silver, gold, copper oxide, zinc oxide, TiO ₂ and SiO ₂ nanoparticles) and three soluble salts (CuSO ₄, ZnSO ₄ and AgNO ₃) on Artemia sp. The physicochemical properties of the nanoparticles involved in this study were analyzed in normal water and marine water. Hydrated and bleached Artemia cysts were allowed to hatch in continuously aerated, filtered sterile salt water containing nanoparticles; hatching of viable nauplii and total hatchlings have been recorded. In parallel, standard Artemia toxicity test was conducted on the nauplii monitoring the viability. In hatching experiments, a reduction in hatching rate was observed along with mortality of newly hatched nauplii. The results of the hatching experiment and of the standard Artemia test showed a good correlation. The toxicity of the nanoparticles was compared and the order of toxicity was estimated as Ag>CuO>ZnO>Au>TiO ₂>SiO ₂. The study thus suggests that the hatching test itself is a reliable assay for determining the toxicity of nanomaterials.