Efficacy of the Hatching Event in Assessing the Embryo Toxicity of the Nano-Sized Tio2 Particles in Zebrafish: A Comparison Between Two Different Classes of Hatching-Derived Variables Publisher Pubmed



Samaee SM¹ ; Rabbani S² ; Jovanovic B³ ; Mohajeritehrani MR⁴ ; Haghpanah V⁴
Source: Ecotoxicology and Environmental Safety Published:2015

Abstract

The aim of the present study was to evaluate the nano-TiO2 toxicity to zebrafish embryos through evaluating the success in hatching in relationship with hours post-exposure instead of considering just the total hatching rate. Zebrafish embryos 4h post-fertilization were exposed to nTiO2 (0, 0.01, 10, and 1000μgmL-1) for 130h. The hatching rate (HR) was calculated for each concentration (treatment). The HR magnitude was significantly (p<0.001) correlated (using simple regression) to hours post-exposure time interval (hpe; 34, 58, 82, 106, and 130), noted as HR.hpe. The HR descriptive statistics (HRds) and the parameters of the regression models (i.e., constant, x, F, and r2) were recruited to define 15 HRds- and 4 h.hpe-derived variables, respectively. The efficacy of the variables was evaluated. Exposure to nTiO2 led to a significant: premature hatching and general decrease in time required for normal hatching; and change in HR and hpe interrelations in a dose-dependent manner. The major change in hatchability between the treatment and control occurred at 58 hpe (62 hpf), when the treatment with nTiO2 induced significant premature hatching compared to only 6% of the hatched embryos in the control at the same time point. EC10 and EC50 values that cause premature hatching at 58 hpe for nTiO2 are 0.073μgmL-1 and 107.2μgmL-1 respectively. In general, this study shows multivariate differences among exposure concentrations of nTiO2 recruiting hatching-derived endpoints. © 2015 Elsevier Inc.