There was no statistically significant difference evident in the IgA levels between smokers and non-smokers (t= 2.01, p= 0.925, n= 55, df= 52). The mean level of IgA absorbance at 450 nm in non-smokers was 0.0597, and the mean level of IgA absorbance at 450 nm of smokers was 0.05996, as shown in Figure 1. The standard error of the nonsmokers being 0.000143114 with the standard error of the smokers 7.21233E-05.