Assessing contamination levels of amprolium and tylosin using the embryo toxicity assay and three biomarkers

This study was conducted to examine the adverse biological effects of two veterinary pharmaceuticals (Amprolium and tylosin) on aquatic organisms. The zebrafish embryo toxicity assays were performed in combination with three biomarkers, including superoxide dismutase (SOD), lipid peroxidation (LPO) and heat shock protein 70(Hsp70). The LPO extent was expressed by malondialdehyde (MDA) in this paper. Logit Loglinear analysis was used to study the effect of exposure concentration and time on survival rate and percent hatched in embryo toxicity tests. The data on SOD, MDA and Hsp70 were analyzed by one-way ANOVA followed by Dunnett's test. The results showed that both pharmaceuticals had no effect on Hsp70 levels in zebrafish. Amprolium and tylosin had significant effect on the survival rate, the percent hatched, SOD and MDA in the range of the experimental concentrations. Furthermore, there was a sharp increase, followed by a decrease in the survival rate, as the exposure concentrations of amprolium or tylosin increased; while SOD and MDA indicated a sharp decrease followed by an increase in survival rates. These results indicated that both pharmaceuticals can be useful to the embryos at low concentrations, while causing acute toxicity at high concentrations. However, two pharmaceuticals cause an acute toxicity effect at concentrations several orders of magnitude higher than detected in the aquatic environments. Both do not result in acute toxicity to zebrafish, but it is recommended that the proper strategy and approach be found to perform chronic low-dose exposure studies.