Fig. 4.

Lung toxicity of the burn pit smoke PM emitted from different waste types and combustion phases. A neutrophil response, B LDH response, C interleukin (IL)-6 response, and D macrophage inflammatory protein (MIP)-2 response. Mice were exposed to the PM (100 µg) by oropharyngeal aspiration and BALF was obtained at 4 and 24 h post exposure. Data are mean ± SEM obtained from 6 mice for each group. *P < 0.05 compared with the saline-exposed (a negative control) group from the same time point. Mice exposed to 2 µg of lipopolysaccharide (LPS) served as a positive control