I need help...

Yeah, I know. Many people have said it before. They may, or may not, be wrong. But in this case as actually do need some help. 

There is some information I need and can I hell as like find it, but somebody must know.

We constantly hear how risky/dangerous/disease causing traditional lit tobacco can be. Let's say I accept all the figures. (I don't). What I want to know is at what timescale from the first drag of the first fag can we expect to see adverse events - and I mean relatively serious adverse effects, like, say, the first signs of COPD or Lung Cancer, or any other measurable result that is, in the literature, put down to being "smoking related". 

If we are to believe what we are told, then these first signs must be observable and attributable - what I want to know - nay, need to know - is what the earliest point of detection is. Why? Well, it's actually quite simple.

As someone who spends a lot of time talking to legislators and practitioners about ecigs, one of the most often heard phrases I hear is "we just don't know what the long terms effects of vaping/ecigs will be". What I want to do is determine how long "long term" needs to be. 

In other words, if, say, 4% of the maladies that are put down to being "smoking related" are observable after a person has been smoking for, say five years - they have become symptomatic - then the "long term" for observing adverse effects in full-switched vapers must needs be the same time period. And if no such maladies are observable in said vapers in that time period (especially since the vast bulk are former smokers) then the "long term effects" are much more easily extrapolated. If, after a further three years, there are still no observed maladies of the type that interest me (and, it seems, Tobacco Control), while another, say, 10% has been added to the reported "smoking related diseases" figures we are told - well, you can see where I'm going with this.

So, dear reader, if you, yourself do not have the info I'm looking for, could you please point this post towards folks you think might have?  And if you have, would you please post said info in the comments?

My undying gratitude, as ever