Why? I get why people generally do not want to be exposed to secondhand smoke, but just how harmful do you think it actually is? Here is what cancer.org says second hand smoke does.
42,000 deaths from heart disease who are non-smokers.
3,400 lung cancer deaths in non smoking adults.
Worsens asthma in up to 1 million asthmatic children.
150,000 to 300,000 low respiratory tract infections in children under 18 months.
Making children much more likely to be put into the ICU when they have flu.
Now all that sounds bad and undeniably secondhand smoke is bad. But how bad? Lets break these down.
"Secondhand smoke causes nearly 34,000 premature deaths from heart disease each year in the United States among nonsmokers.Secondhand smoke causes nearly 34,000 premature deaths from heart disease each year in the United States among nonsmokers."
To Quote: "Therefore, the committee concurs with the current consensus in the 2006 surgeon general’s report that “the evidence is sufficient to infer a causal relationship between exposure to secondhand smoke and increased risks of coronary heart disease among both men and women.” While the committee found strong evidence of this association, the evidence for determining the precise magnitude of the increased risk—that is, the number of cases of disease that are attributable to secondhand-smoke exposure— is not as strong. The committee therefore did not estimate the size of the effect. "
The truth is we don't know the precise magnitude of impact secondhand smoke has on heart disease. It has a connection--but how much, how often, how long, and so on. As that report stated, it is hard to put a number on it. Its why you see different numbers cited every time.
Their literature on heart disease also suggests that their are many contributing factors. Smoking is one of them, but its hard to say secondhand smoke is.
Conclusion: Its tough to say that these kids are going to develop heart disease. Its tough to actually quantify how much exposure is actually needed (or even what counts as exposure). Smoking in a car with windows up or windows barely cracked is going to result in much more exposure than four windows rolled all the way down while going 65 on a free way.
3,400 lung cancer deaths in non-smoking adults. This one is pretty well researched as the links between lung cancer and smoking are extremely well-established.
About 200,000 people are diagnosed with lung cancer in the US.
About 20,000 people die from lung cancer after exposure to radon gas. Ever heard of it?
The link between secondhand smoke and lung cancer is considerably weaker. It is hard to measure what exposure level is dangerous and it really isn't something that consistent anyway. It does seem consistent that long term smokers (10+ years) greatly improve their chances if they quit. Your lungs heal.
Lung cancer is probably a small worry. Do check for radon gas.
"Worsens" asthma. Asthma actually has a fairly low mortality and is pretty treatable.
No offense, but knowing smoking around an asthmatic person, kid or not, seems like they're an asshole.
Although smoking worsens asthma, its not clear its a cause. Check out some data here. Note, as smoking declines, asthma climbs. Asthma is always climbing.
Smoking can trigger asthma attacks and its a real dick move to smoke around asthmatic people, but it doesn't cause asthma and probably doesn't warrant a general ban.
Lower Respiratory Tract Infects in Children Under 18 months and FLU ICU:
Conclusion: Secondhand smoke is bad, but it isn't the demon its made out to be. It probably isn't going to cause heart disease in kids (or when they become adults) and it probably isn't going to give them lung cancer. Even in adults, its not clear how much exposure is needed to cause health effects but it probably requires a more regular exposure.
Its not child abuse for a parent to smoke around their kid. The WORST part about a parent smoking in a car probably has more to do with setting a bad example. If they're asthmatic, don't smoke around them period, adult or child. If they're infants, don't smoke around them. If someone is sick with respiratory issues, don't smoke around them. These seem like good sense to me regardless.