Two-tailed unpaired t-tests were used to assess differences in the lung CYP2A protein levels between treatment groups in AGM study 1. Two-way ANOVA tests were used to assess differences in the lung CYP2A protein levels between treatment groups in AGM study 2. Tukey’s multiple comparison post hoc tests were subsequently used to assess differences in lung CYP2A protein levels between treatment groups and treatment interactions in AGM study 2. The D’Agostino-Pearson omnibus normality test was used to determine the normality of signal distribution, followed by correlation analyses to assess the relationships between lower and upper lung CYP2A protein levels within individual AGMs. Data from both AGM studies were found to be normally distributed; thus, Pearson’s correlations were used to assess the relationship between the lower and upper lung.