Verwijdering carcinogene stoffen in tabak: geen effect op longkanker

Wanneer alle bekende kankerverwekkende stoffen uit tabalk zouden worden
verwijderd zou dat de kans op longkanker met een minieme 4%
verkleinen. Dat is de opvallende uitkomst van een nieuw onderzoek dat
gepubliceerd is in het Maart-nummer van Cancer Epidemiology, Biomarkers &
Prevention.

Dit opmerkelijke resultaat plaatst een bom onder de pogingen van de
anti-rokenbeweging en bekende senatoren als Edward Kennedy om de tabaksindustrie
onder control te stellen van de FDA, de Amerikaanse toezichthouder op de
volksgezondheid.

En de tabaksindustrie kan in haar vuistje lachen volgens
anti-rokenonderzoeker Michael Siegel: “As I’ve argued before, the FDA tobacco
legislation is really a mechanism to transfer the deception about low-yield
cigarettes from the tobacco companies to the government. It takes the tobacco
companies off the hook, allowing them to smile all the way to the bank as the
very low-yield health claims they have been found guilty of making are now made
by the federal government.“

Toxicant deliveries (by machine smoking) are compiled and associated
cancer risks are calculated for 13 carcinogens from 26 brands of conventional
cigarettes categorized as “regular” (R), “light” (Lt), or “ultralight” (ULt),
and for a reference cigarette. Eight “potentially reduced exposure product”
(PREP) cigarettes are also considered. Because agency-to-agency differences
exist in the cancer slope factor (CSF) values adopted for some carcinogens, two
CSF sets were used in the calculations: set I [U.S. Environmental Protection
Agency (EPA)–accepted values plus California EPA–accepted values as needed to
fill data gaps] and set II (vice versa). The potential effects of human smoking
patterns on cigarette deliveries are considered. Acetaldehyde, 1,3-butadiene,
and acrylonitrile are associated with the largest calculated cancer risks for
all 26 brands of conventional cigarettes. The calculated risks are proportional
to the smoking dose z (pack-years). Using CSF set I and z = 1 pack-year (7,300
cigarettes), the calculated brand-average incremental lifetime cancer risk values are R, 6 x 10–5; Lt, 5 x 10–5; and ULt, 3 x 10–5 (cf. typical U.S. EPA risk benchmark of
10–6). These values are similar, especially given the tendency of smokers to
“compensate” when smoking Lt and ULt cigarettes. is the brand-average per pack-year subtotal risk for the measured human
lung carcinogens. Using CSF set I, the values for R, Lt, and ULt cigarettes account for 2% of epidemiologically
observed values of the all-smoker population average per pack-year risk of lung
cancer from conventional cigarettes. R_PREP (%) is a science-based
estimate of the possible reduction in lung cancer risk provided by a particular
PREP as compared with conventional cigarettes. Using CSF set I, all
R_PREP values are <2%. The current inability to account for the
observed health risks of smoking based on existing data indicates that current
expressed/implied marketing promises of reduced harm from PREPs are unverified:
there is little reason to be confident that total removal of the currently
measured human lung carcinogens would reduce the incidence of lung cancer among
smokers by any noticeable amount.

Calculated Cancer Risks for Conventional and “Potentially Reduced
Exposure Product” Cigarettes
Commentaar Michael Siegel