Subject: What are the long term effects of smoking

Hello.  My father is normally a quite knowledgable man.  But not concerning the 
matter on smoking.  He smokes.  He says that second hand smoke is "a bunch of 
bull". He says that there is no such thing as second hand smoke, and unless you 
smoke, yours lungs are clear as a bell.  I said that my friend, who has rarely 
been exposed to smoke, has much clearer lungs than I do.  He completely 
disagrees with me.  He says that second hand smoke is a government conspiracy in 
an attempt to get more money ( something like that).  He says that if a person 
smokes for twenty years, doesn't develop any long-term effects (i.e. emphasema, 
lung cancer, etc.) then in five years or so his lungs will completely clear and 
there would be no tar or any other smoking related substances left on the lung.  
I find this preposterous. What  I have leaned in recent years in school 
completely contradicts his statements.  So, my questions are is second hand 
smoke a falicy?  How quickly does a smoker without long term effects lungs clear 
up?  Thank you for your time and consideration of my questions.

Re: What are the long term effects of smoking