COMMENT ON "HEALTH EFFECTS OF EXPOSURE TO ENVIRONMENTAL TOBACCO SMOKE"

CHAPTER 5
Reproductive Effects

5.2 Female Fertility and Fecundability

This report states that "covariates related to sexual practices are important to consider, including frequency of coitus,..." It then proceeds to treat this covariate as if it is completely irrelevant by citing defective studies and defective reviews of such studies in which it was not considered, including the 1980 Surgeon General Report. By this dishonest and deceitful means, this report claims that "active smoking by women has been found to be associated with decreased fertility in a number of studies,..." (5.5 Chapter Summary and Conclusions, page 5-11). In "Disorders of the placenta, fetus, and neonate, diagnosis and clinical significance. (New York: CV Mosby Co., 1992, page 78), RL Naeye states:

In the CPS it took longer for smokers than for non-smokers to conceive. However, this association completely disappeared when confounding risk factors were taken into consideration. The two confounding risk factors that were responsible for the delay that smokers experienced in becoming pregnant were being over 34 years in age and having blue-collar employment outside of the home. It has long been known that it takes longer to become pregnant at advanced maternal age. The association of blue collar work with taking longer to become pregnant may be due to less frequent coitus. In the CPS, women who had such employment usually had coitus only once a week during pregnancy whereas gravidas not working outside of their homes had coitus more frequently."

Naeye's study population is the 56,000+ pregnancies of the Collaborative Perinatal Study of the National Institute of Neurological and Communicative Disorders and Stroke. Considering the importance of this variable, its inclusion should have been a requirement for considering any study. But again, the anti-smokers have trampled on the rules of good epidemiology in order to exploit smokers' socioeconomic disadvantage.

This report also claims that "...tobacco smoke appears to be anti- estrogenic,..." (5.5 Chapter Summary and Conclusions, page 5-11), and that "cigarette smoking appears to be anti-estrogenic" (5.2.4. Discussion and Conclusions, page 5-6). This is pure misrepresentation, because hormone studies have failed to consistently demonstrate differences between smokers and non-smokers. To perpetrate this deceit, the studies and reviews cited are old (Baron et al. 1990; MacMahon et al. 1982; Michnovicz et al. 1986; Seyler et al. 1986; Barrett-Connor 1990; Cannick and Barbieri 1990; Stillman et al. 1986) and do not include better, more recent work. Specious theories, with supposed support from animal studies, are invoked to "explain" infertility by oocyte/follicle destruction by "nicotine or PAHs" (5.2.3 Animal Studies of Female Fertility and Fecundability and Tobacco Smoke Exposure, page 5-7). Exposure to PAHs from cigarette smoke is in fact trivial compared to exposure from dietary sources, even for smokers. Reference: HA Hattemer-Frey, CC Travis. Benzo-a-pyrene: Environmental partitioning and human exposure. Toxicology and Industrial Health 1991;7(3):141-157: This analysis found that "the food chain is the dominant pathway of human exposure, accounting for about 97% of the total daily intake of BaP. Inhalation and consumption of contaminated water are only minor pathways of human exposure [2% from air, and 1% from water]. The long-term average daily intake of BaP by the general population is estimated to be 2.2 micrograms (ug) per day. Cigarette smoking and indoor activities do not substantially increase human exposure to BaP relative to background levels of BaP present in the environment." And, "... average smokers (i.e., individuals who smoke 20 cigarettes a day) are taking in an additional 780 ng of BaP daily, which means that smokers get an additional 16% BaP from smoking" [based on pre-1979 cigarettes. Newer low-tar cigarettes contain about half that]. Hattemer-Frey & Travis' research was "sponsored by the U.S. Environmental Protection Agency under Interagency Agreements applicable under Martin Marietta Energy Systems, Inc., Contract No. DE-AC05-84OR21400."