Biological Impact of Exposure to Extremely Fine-Grained Volcanic Ash

Figure 7

Nitric oxide production on peritoneal macrophages by volcanic ash after 24 hours. Macrophages were exposed to 80 µg/cm³ (green), 320 µg/cm³ (yellow), and 1280 µg/cm³ (purple) of volcanic ash and 400 µg/cm³ of titanium dioxide (blue). The negative control was cells without any treatment (red). ; (one-way ANOVA with Dunnett’s posttest).