Epidemiological studies have demonstrated that tobacco smoke is a major cause of both cancer and vascular diseases. More than 3800 chemicals are present in tobacco smoke, which may cause oxidative stress via biotransformation or by macrophage activation. In 1954, Richard Doll and Bradford Hill published the first prospective evidence on cigarette smoking and lung cancer. In 1962, Framingham investigators published data showing that smoking increased the risk of heart disease. Nevertheless, despite the strong evidence, uncertainty was manufactured and enlarged. This strategy is a common practice to reduce the public health implications from epidemiological findings and was used not only by tobacco companies but also by other industrial arms, including asbestos and lead factories. For almost half a century, the tobacco companies hired scientists to dispute first that smokers were at greater risk of dying of lung cancer; second, the role of tobacco use in heart disease; and finally, the evidence that environmental tobacco smoke increased disease risk in non-smokers. The effect of in-utero exposures on health in childhood and later in life is a growing area of research interest, with major public health implications. Children are vulnerable to the adverse effects of environmental tobacco smoke as their lungs and immune system are undergoing further development. The first publications of detrimental health effects of parental smoking on children’s respiratory health were published in the early 1970s. Exposure to environmental tobacco smoke in the first 2 years of life has been estimated in some European countries by Pattenden et al. and ranged from 19% in Germany to 70% in Bulgaria.