Fig. 6

Total protein levels (a) in bronchioalveolar lavage (BAL) fluid of BALB/c mice exposed to particles for 24 h by intratracheal (IT) instillation. Neutrophil cell counts (b) were determined from cytospin preparations of BAL. All values are presented as mean fold effect (FE) over control ± standard error (n = 5). Two way ANOVA; Total protein, Dose main effect, p < 0.001, Dose 250 vs. 0, 50 or 100 (†), Tukey test, p < 0.001; Neutrophils, PM × Dose interaction, p = 0.004, asterisks (*) represent effects significantly different from Dose 0 control, Tukey test, p < 0.05. Heatmap with hierarchical cluster analysis of toxicity endpoints (cell differential counts and biochemical endpoints) (c) assessed in BALB/c mice 24 h after exposure to particles by intratracheal instillation, summarized as potency estimates (slopes of the dose response). Within the heatmaps, red color represents increased toxic potency of particles (increased biochemical measures or cell counts; positive β), whereas green color represents decreased toxic potency, with the exception of macrophages, whereby green color representing a loss of cells is a measure of increased particle potency (negative β)