Investigating potential toxicity of phenanthrene adsorbed to nano-ZnO using Daphnia magna

Abstract

This study was conducted to evaluate the bioavailability of phenanthrene adsorbed onto nano-ZnO by comparing its toxicity to Daphnia magna exposed to nano-ZnO only for 24 and 48 h. The LC₅₀ values of phenanthrene-loaded and phenanthrene-free nano-ZnO were determined. SPSS software, independent-samples t-test technique, and Pearson correlation coefficients were used for statistical analysis. The toxicity of phenanthrene-loaded nano-ZnO at 24 and 48 h of exposure were 1.5 ± 0.1 and 1.0 ± 0.1 mg L⁻¹, respectively, 1.7 and 2.1 times higher than that of phenanthrene-free nano-ZnO, which were 2.6 ± 0.2 and 2.1 ± 0.1 mg L⁻¹, respectively. It may be concluded that nano-ZnO serves as carrier of phenanthrene from the medium to D. magna; therefore, when designing standard criteria and disposal legislations in the use of nano-ZnO in different fields, the bioavailability problems of pollutants adsorbed to such nanoparticles should be regarded.

Keywords:

• nanoparticle
• ZnO
• LC₅₀
• bioavailability
• bioassay
• phenanthrene