IL6 (black bars) and IL8 (grey bars) production by HK-2 cells in the presence of the panel of engineered nanomaterials. The cells were exposed to the sub-lethal concentrations of the NMs for 24 hr with cytokine secretion measured utilising the FACSArray. Values represent mean ± SEM (n = 3), significance indicated by * = p < 0.05 and ** = p < 0.005, when material treatments are compared to the control. A) NM 110 B) NM 111 C) NRCWE 402 D) NM 400 E) NRCWE 002 F) NRCWE 003 G) NRCWE 001 H) NRCWE 004 I) NM 300 J) NM 101. The Figure has been arranged according to the biological effect of individual NMs.