Assessment of trifloxystrobin uptake kinetics, developmental toxicity and mRNA expression in rare minnow embryos

Trifloxystrobin (TFS) is the widely used strobilurin fungicide. However, little information is so far available regarding the uptake kinetics and developmental toxicity of TFS to fish. The present study was conducted to investigate the uptake kinetics, potential environment risk and toxicity of TFS on Gobiocypris rarus embryos. Results revealed that increased malformation, decreased body length and heart rate, affected spontaneous movement and swimming speed provide a gradual concentration-dependent manner; values of 144 h LC50 (median lethal concentration) and EC50 (median effective concentration) were 1.11 and 0.86 μg L(-1). Continuous exposure to TFS resulted in a steady accumulation with no evidence of elimination. Enzyme activities were significantly changed; reactive oxygen species and DNA damage were significantly induced after TFS treatment. Certain genes related to cell apoptosis (p53), metabolism (cyp1a), stress response (hsp70) and blood vessels (vezf1) development were all significantly up-regulated. This is the first study to define uptake kinetics and to focus on behavioral consequences, physiological changes and mRNA expression following TFS exposure in the early life stages of fish. Our results suggest that TFS is highly toxic to fish embryos.