Figure 8

Cytokine level in the broncho-alveolar lavage fluid. The animals exposed to 15 nm silver nanoparticles had significantly increased levels of IL-1β (p < 0.05), MCP-1 (p = 0.06) and MIP-2 (p < 0.01) in the BALF at 24 hours exposure compared to the controls. At 24 hours after exposure, the levels of IL-1β (p < 0.05) and MCP-1 (p < 0.01) were also significantly increased compared to the animals exposed to 410 nm silver particles. At 7 days after exposure, the cytokine levels returned to normal.