Fig. 6

Comparison on the a deposition fraction and b normalized deposition fraction between MPPD model prediction and animal study results. Bars for the model predictions showed the mean ± standard deviation of male and female rats estimations. Model predictions were identical for regular and mentholated little cigars because they had a similar particle size distribution. Bars for animal study represent the mean ± standard error for the merged data from both male and female rats (n = 10). Kruskal–Wallis test, with a post-hoc Dunn’s test was conducted to compare the significance between the animal study and model prediction results. * indicates P < 0.05, ** indicates P < 0.01, and *** indicates P < 0.001