| Chemical compounds | Carcinogenicity | Ref. |
| carbon monoxide | Not listed | |
| benzene | Group 1 | [22] |
| formaldehyde | Group 1 | [23] |
| polycyclic aromatic hydrocarbons (PAHs) | Group 1, Group 2A and group 2B | [24] |
| hydrogen cyanide | Not listed | [22] |
| benzo (a) pyrene (BaP) | Group 1 | [25] |
| heterocyclic aromatic amines | Not listed | [26] |
| aldehydes | Group 1 | [27] |
| phenolic compounds | Not listed | [22] |
| volatile hydrocarbons, | Group 2A | [22] |
| toluene | Group 3 | [22] |
| furan | Group 2B | [22] |
| 2-methylfuvan | Not listed | [22] |
| isobutylene | Group 1A | [28] |
| terpenes and terpenoids | Group 2B | [29] |
| tetrahydrocannabinol | Not listed | [30] |
| cannabidiol | Group 2B | [31] |