Fig. 2From: Assessment of pesticides in surface water samples from Swedish agricultural areas by integrated bioanalysis and chemical analysisOxidative stress response measured in human adrenocortical H295R cells transiently transfected with an Nrf2-sensitive luciferase reporter. Cells were exposed to concentrated water samples for 24 h prior to measurement of luciferase activity (mean, n = 4). Bioactivity was normalized to vehicle control, set to 1. Solid line indicates the cut-off value of ≥ 2 fold induction. For standard deviation, refer to Additional file 4: Table S4Back to article page