Fig. 5

Association of DNA adduct levels with tobacco smoking and alcohol consumption. Box plots of etheno-dA show nominal p-values less than 0.05 by the Mann-Whitney U test in comparisons of (a) tobacco smoking, (b) alcohol consumption or (c) both. The center line of the box indicates the median, and the top and bottom edges of the box indicate their IQR. The whiskers show the maximum or minimum within a range of 1.5 times the IQR from the edge of the box. Outliers are indicated by circles (°) that are 1.5 to 3 times the IQR from the top or the bottom of a box and by stars (*) that are more than 3 times the IQR from the top or the bottom of a box. Zero values were excluded from the box plots