Effect of silver nanoparticles on the acute toxicity of mercury in Zebrafish (Danio rerio)

It is important to evaluate the co-exposure effects of chemical contaminants on aquatics. Mercury ions and silver nanoparticles are among the chemicals mixed together through amalgamation. This study was aimed to evaluate the effect of the presence of a non-lethal concentration of silver nanoparticles in water on the acute toxicity of inorganic mercury in zebrafish. In the presence or absence of silver nanoparticles, therefore, median lethal concentrations (LC50) of mercury were calculated according to the OECD standard guideline. The comparison of LC50s showed that the presence of 0.1 mg silver nanoparticles per liter, reduces the acute toxicity of mercury in the zebrafish by 1.5-fold (LC50 increased from 0.135 ± 0.010 to 0.206 ± 0.002 mg/L). Although the reduction of mercury toxicity in the presence of silver nanoparticles is probably due to the reduction of its bioavailability as a result of amalgamation or adsorption of mercury ions on the surface of nanoparticles, but further studies are needed to understand the exact mechanism of interaction between mercury and silver nanoparticles in aquatic environment.