Figure 4

The relative expression level of GSTmu was determined using select reference genes, including the most (H2A) or least stable (Atb) reference genes, for normalization in the brackish water flea D. celebensis exposed to (A) B[a]P, (B) BPA, and (C) Hg. Different letters indicate significant differences between groups using different reference genes (ANOVA, Tukey’s post-hoc analysis, p < 0.05).