Results of the study conducted by Dr. Robert McMillen and others (2003), show that 70% of US adult smokers do not prohibit or do not have smoking prohibitions at home which puts their spouses', children's and other inhabitants' health at risk. The same study confirmed that parent's cigarette consumption influence their children's exposure to Environmental Tobacco Smoke (ETS) (McMillen, 2003).
According to Randall (2006), secondhand smoke, also known as passive smoke, is the involuntary breathing of other people's smoke. In his study, he found out that more than 40% of British children live in a house with at least one person smoking. And secondhand smoke being worse than firsthand smoke, these children is even more in danger of acquiring illnesses such as asthma.
Asthma is said to be the most common chronic illness in children (Hansen, 2002). And because studies show that a large number of US homes do not prohibit smoking inside the house, there is a great possibility that the children acquire or inhale some of the secondhand smoke from cigarette and tobacco.