I see a lot of information on this site about half life. My question is: What is the general concentration of a persons body who is a daily smoker? I know this varies by a person's size/weight/activity level/etc but what I'm just looking for a general answer. i.e. If it takes 30 days to get traces out of a persons level and they have to pass at 49 ng/ml. Does that mean 49 ng/ml * 10 days would be 98. 98 ng/ml * 10 more days = 196. And 196 * 10 more days = 392. So the average daily smoker has a ng/ml level of 392? I may be totally off basis but I am curious what a generalized average ng/ml level of a daily smoker is.