Figure 1

DFP-exposed zebrafish larvae displayed reduced motility and AChE inhibition. (a) As experimental set-up, 5 dpf larvae were exposed to 15, 20, 30 or 50 µM DFP or vehicle (1% DMSO) and larval lethality, phenotypic defects, motor activity, and AChE activity were studied during the next 6 h. (b) Lethality rates of 5 dpf larvae exposed for 6 h to 15, 20, 30 or 50 µM DFP and selection of 15 µM DFP as optimal concentration (LC20). (c) Residual concentrations of DFP measured at different time points from a 15 µM solution diluted in fish water (E3 medium). (d,e) Morphology of 5 dpf larvae exposed for 6 h to either vehicle (d) or 15 µM DFP (e). (f) Scheme depicting measurements of zebrafish larva morphology. (g–i) Quantification of eye diameter (g), head size (h) and body length (i) in larvae exposed for 6 h to either vehicle (n = 26) or 15 µM DFP (n = 26) (Student’s unpaired t-test: n.s., non-significant; *, p < 0.05). (j) Quantification of AChE activity in larvae exposed to 15 µM DFP (n = 5) or vehicle (n = 5), for 2, 4, and 6 h (two-way ANOVA with Sidak’s multiple comparisons test: ****, p < 0.0001). (k) Motor activity of 5 dpf larvae exposed to either 15 µM DFP (n = 44) or vehicle (n = 12) (two-way ANOVA with Sidak’s multiple comparisons test: **, p < 0.01; ***, p < 0.001).