Nomenclature terms of importance in this work for consideration of the risk due to toxicants in tobacco smoke
| Term . | Meaning . | Units . |
|---|---|---|
| i | A toxicant of interest (e.g., 1,3-butadiene, benzene, N-nitrosonornicotine, NNK, etc.) | — |
| Ai | Per cigarette smoke delivery (aka yield of toxicant i) | μg/cigarette |
| z | Total smoking dose in pack-years | pack-years |
\(\mathrm{CDI}^{i}_{1}\) | Average (chronic) rate of daily intake of toxicant i by smoking when the total smoking dose is 1 pack-year and, in this work, when the dose is averaged over 70 y | mg/kg d |
\(\mathrm{CDI}^{i}_{\mathit{z}}\) | Average (chronic) rate of daily intake of toxicant i by smoking when the total smoking dose is z pack-years and, in this work, when the dose is averaged over 70 y | mg/kg-d |
| CSFi | Cancer slope factor for carcinogen i (also known as the cancer potency of i) | (mg/kg-d)−1* |
\(\mathrm{ILCR}^{i}_{1}\) | Incremental calculated lifetime cancer risk for carcinogen i for a z = 1 pack-year smoking dose | risk for 1 pack-year |
\(\mathrm{ILCR}^{i}_{\mathit{z}}\) | Incremental calculated lifetime cancer risk for carcinogen i for a smoking dose of z pack-years | risk for z pack-years |
\(\overline{\mathrm{ILCR}}^{i}_{1}\) | Average calculated value of the \(\mathrm{ILCR}^{i}_{1}\) for a given group of cigarettes of a certain type (e.g., the average for all light cigarettes) | risk for 1 pack-year |
| subΣ | A subtotal for a specific subset of carcinogens | — |
| subΣ-lung | A subtotal for a specific subset of human lung carcinogens | — |
\(\mathrm{ILCR}^{\mathrm{sub{\Sigma}}}_{1}\) | A subtotal of individual calculated \(\mathrm{ILCR}^{i}_{1}\) for all carcinogens measured, with the smoking dose z = 1 pack-year | risk for 1 pack-year |
\(\overline{\mathrm{ILCR}}_{1}^{\mathrm{sub{\Sigma}}}\) | Average value of calculated \(\mathrm{ILCR}^{\mathrm{sub}{\Sigma}}_{1}\) for a given group of cigarette brands of a certain type (e.g., the average for light brands) | risk for 1 pack-year |
\(\mathrm{ILCR}^{\mathrm{sub{\Sigma}}{-}\mathrm{lung}}_{1}\) | SubΣ of individual calculated \(\mathrm{ILCR}^{\mathit{i}}_{1}\) for all human lung carcinogens that have been measured (analytically), for a z = 1 pack-year smoking dose | risk for 1 pack-year |
\(\overline{\mathrm{ILCR}}^{\mathrm{sub{\Sigma}}{-}\mathrm{lung}}_{1}\) | Average value of calculated \(\mathrm{ILCR}^{\mathrm{sub{\Sigma}{-}lung}_{1}}\) for a given group of cigarette brands of a certain type (e.g., the average for light brands) | risk for 1 pack-year |
\(\overline{\mathrm{ILCR}}^{\mathrm{obs{\Sigma}}{-}\mathrm{lung}}_{\mathit{z}}\) | Actual observed risk from smoking z pack-years | risk for z pack-years |
| M | Percent match between \(\overline{\mathrm{ILCR}}^{\mathrm{sub{\Sigma}{-}lung}_{1}}\) for conventional cigarettes and Ω1lung | % |
| RPREP | Amount by which the calculatable per pack-year risk of lung cancer is reduced by switching from conventional cigarettes to a particular PREP | % |
\({\Omega}^{\mathrm{lung}}_{1}\) | Observed total ILCRΣ−lung risk per pack-year for lung-cancer for z = 1 pack-year as averaged over all smokers and all smokers' doses in a particular real population (not a subΣ, but the full observed Σ) | risk per pack-year |
| Term . | Meaning . | Units . |
|---|---|---|
| i | A toxicant of interest (e.g., 1,3-butadiene, benzene, N-nitrosonornicotine, NNK, etc.) | — |
| Ai | Per cigarette smoke delivery (aka yield of toxicant i) | μg/cigarette |
| z | Total smoking dose in pack-years | pack-years |
\(\mathrm{CDI}^{i}_{1}\) | Average (chronic) rate of daily intake of toxicant i by smoking when the total smoking dose is 1 pack-year and, in this work, when the dose is averaged over 70 y | mg/kg d |
\(\mathrm{CDI}^{i}_{\mathit{z}}\) | Average (chronic) rate of daily intake of toxicant i by smoking when the total smoking dose is z pack-years and, in this work, when the dose is averaged over 70 y | mg/kg-d |
| CSFi | Cancer slope factor for carcinogen i (also known as the cancer potency of i) | (mg/kg-d)−1* |
\(\mathrm{ILCR}^{i}_{1}\) | Incremental calculated lifetime cancer risk for carcinogen i for a z = 1 pack-year smoking dose | risk for 1 pack-year |
\(\mathrm{ILCR}^{i}_{\mathit{z}}\) | Incremental calculated lifetime cancer risk for carcinogen i for a smoking dose of z pack-years | risk for z pack-years |
\(\overline{\mathrm{ILCR}}^{i}_{1}\) | Average calculated value of the \(\mathrm{ILCR}^{i}_{1}\) for a given group of cigarettes of a certain type (e.g., the average for all light cigarettes) | risk for 1 pack-year |
| subΣ | A subtotal for a specific subset of carcinogens | — |
| subΣ-lung | A subtotal for a specific subset of human lung carcinogens | — |
\(\mathrm{ILCR}^{\mathrm{sub{\Sigma}}}_{1}\) | A subtotal of individual calculated \(\mathrm{ILCR}^{i}_{1}\) for all carcinogens measured, with the smoking dose z = 1 pack-year | risk for 1 pack-year |
\(\overline{\mathrm{ILCR}}_{1}^{\mathrm{sub{\Sigma}}}\) | Average value of calculated \(\mathrm{ILCR}^{\mathrm{sub}{\Sigma}}_{1}\) for a given group of cigarette brands of a certain type (e.g., the average for light brands) | risk for 1 pack-year |
\(\mathrm{ILCR}^{\mathrm{sub{\Sigma}}{-}\mathrm{lung}}_{1}\) | SubΣ of individual calculated \(\mathrm{ILCR}^{\mathit{i}}_{1}\) for all human lung carcinogens that have been measured (analytically), for a z = 1 pack-year smoking dose | risk for 1 pack-year |
\(\overline{\mathrm{ILCR}}^{\mathrm{sub{\Sigma}}{-}\mathrm{lung}}_{1}\) | Average value of calculated \(\mathrm{ILCR}^{\mathrm{sub{\Sigma}{-}lung}_{1}}\) for a given group of cigarette brands of a certain type (e.g., the average for light brands) | risk for 1 pack-year |
\(\overline{\mathrm{ILCR}}^{\mathrm{obs{\Sigma}}{-}\mathrm{lung}}_{\mathit{z}}\) | Actual observed risk from smoking z pack-years | risk for z pack-years |
| M | Percent match between \(\overline{\mathrm{ILCR}}^{\mathrm{sub{\Sigma}{-}lung}_{1}}\) for conventional cigarettes and Ω1lung | % |
| RPREP | Amount by which the calculatable per pack-year risk of lung cancer is reduced by switching from conventional cigarettes to a particular PREP | % |
\({\Omega}^{\mathrm{lung}}_{1}\) | Observed total ILCRΣ−lung risk per pack-year for lung-cancer for z = 1 pack-year as averaged over all smokers and all smokers' doses in a particular real population (not a subΣ, but the full observed Σ) | risk per pack-year |
NOTE: For each ILCR value, a specific CDI is assumed. The units of each ILCR are “fractional risk.” For exposed individual, an ILCR = 0.001 indicates a 1 in 1,000 chance of cancer above the background risk.
Because a CSF is a slope of cancer incidence versus CDI, a CSF may alternately be viewed as having units of risk/(mg/kg d).