Always wondered about this -- the difference between drawing a raw draft into your lungs and breathing the air in a smoky room is probably a million to one in concentration. Plus, the smoke in the room air is at room temperature and the volatiles are not as active as they are when heated.
From BMJ (wholly owned by the British Medical Association):
Environmental tobacco smoke and tobacco related mortality in a prospective study of Californians, 1960-98
Abstract
Objective To measure the relation between environmental tobacco smoke, as estimated by smoking in spouses, and long term mortality from tobacco related disease.
Design Prospective cohort study covering 39 years.
Setting Adult population of California, United States.
Participants 118,094 adults enrolled in late 1959 in the American Cancer Society cancer prevention study (CPS I), who were followed until 1998. Particular focus is on the 35 561 never smokers who had a spouse in the study with known smoking habits.
Main outcome measures Relative risks and 95% confidence intervals for deaths from coronary heart disease, lung cancer, and chronic obstructive pulmonary disease related to smoking in spouses and active cigarette smoking.
Results For participants followed from 1960 until 1998 the age adjusted relative risk (95% confidence interval) for never smokers married to ever smokers compared with never smokers married to never smokers was 0.94 (0.85 to 1.05) for coronary heart disease, 0.75 (0.42 to 1.35) for lung cancer, and 1.27 (0.78 to 2.08) for chronic obstructive pulmonary disease among 9619 men, and 1.01 (0.94 to 1.08), 0.99 (0.72 to 1.37), and 1.13 (0.80 to 1.58), respectively, among 25 942 women. No significant associations were found for current or former exposure to environmental tobacco smoke before or after adjusting for seven confounders and before or after excluding participants with pre-existing disease. No significant associations were found during the shorter follow up periods of 1960-5, 1966-72, 1973-85, and 1973-98.
Conclusions The results do not support a causal relation between environmental tobacco smoke and tobacco related mortality, although they do not rule out a small effect. The association between exposure to environmental tobacco smoke and coronary heart disease and lung cancer may be considerably weaker than generally believed.
The whole paper is available online at the link Looking around the BMJ website is fascinating, I will be adding it to my blogroll next time I do an update. From their About page:
About BMJ
The BMJ is an international peer reviewed medical journal and a fully 'online first' publication. Our publishing model continuous publication means that all articles appear on bmj.com before being included in an issue of the print journal. The website is updated daily with the BMJ's latest original research, education, news, and comment articles, as well as podcasts, videos, and blogs.
All the BMJ's original research is published in full on bmj.com, with open access and no limits on word counts. We do not charge authors or readers for research articles, nor for other articles arising from work funded by open access grants. The BMJ's vision is to be the world's most influential and widely read medical journal. Our mission is to lead the debate on health and to engage, inform, and stimulate doctors, researchers, and other health professionals in ways that will improve outcomes for patients. We aim to help doctors to make better decisions. The BMJ team is based mainly in London, although we also have editors elsewhere in Europe and in the US.
A nice change from the restrictive policies of companies like Elsevier (which has been caught publishing fake journals to promote specific drugs -- Astroturfing at its worst)
