| Toxicant | Level in μg/mg nicotine (international brands)* | Level in μg/mg nicotine (Canadian brands)† | Criteria for selecting the value |
| NNK | 0.072 | 0.047 | Median value of the data set |
| NNN | 0.114 | 0.027 | Median value of the data set |
| Acetaldehyde | 860 | 670 | 125% of the median value of the data set |
| Acrolein | 83 | 97 | 125% of the median value of the data set |
| Benzene | 48 | 50 | 125% of the median value of the data set |
| Benzo[a]pyrene | 0.011 | 0.011 | 125% of the median value of the data set |
| 1,3-Butadiene | 67 | 53 | 125% of the median value of the data set |
| Carbon monoxide | 18 400 | 15 400 | 125% of the median value of the data set |
| Formaldehyde | 47 | 97 | 125% of the median value of the data set |
*Based on data from Counts et al.11
†Based on the data reported to Health Canada minus the brands with NNN/mg nicotine levels over 0.1, which eliminates most US and Gauloise brands (http://www.hc-sc.gc.ca/hl-vs/tobac-tabac/legislation/reg/indust/constitu_e.html).12
NNK, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone; NNN, N′-nitrosonornicotine.