Carbon Black Particle Exhibits Size Dependent Toxicity in Human Monocytes

Figure 2

Percentage of the metabolic activity of THP-1 cells upon exposure to varying concentrations of carbon particles, as determined by the MTT assay. Cells were exposed to 50, 100, 200, 400 and 800 μg/mL of nano- and microcarbon particles for 24 h. The results are expressed as a percentage relative to controls and are presented as mean ± SEM of three independent replicate experiments. Significance is indicated by ^∗𝑃<0.05, ^∗∗𝑃<0.01 and ^∗∗∗𝑃<0.001, versus control. ^#𝑃<0.05 indicates significant difference between the particle sizes.