that is not true.... Whether its a salt or an organic compound that gets broken down, nitrogen is nitrogen and is used exactly the same in every plant. It goes in through the roots, and is used to build different parts of the plants. Not directly like a brick would build a house, but like all the components of concrete mixing together combining and changing into a different form.
Commercial farmers dont flush, so either EVERYTHING we have ever eaten is as bad for us as unflushed weed, or flushing doesnt do anything.
Its like the fruit thing i was saying. Take a bite of an unripe fruit and tell me you dont taste "chemicals" over sugars.
So if i ate nothing but the best grown organic/synthetic fed fruit but it wasnt flushed (like was done for the entire existence of man) than i would be ill and have a build up of said "chemicals" in my liver, kidneys, etc... Which no one has....
Youve smoked for over 40 years.... No matter what you smoke, smoke going into your lungs, no matter how pure, is not good/"natural" and will lead to premature failure or be more prone to problems. Likewise with alcohol. There is worse shit in our air than the shittiest weed grown with the shittiest nutrients. Let alone what is in cigarettes.
Unless you foliar feed with high dose nutes very shortly before harvesting, there shouldnt be any of the original compounds from your nutrients, in your buds. If the nutrients are powder/crystalized when used that could lead to airborne chemicals that could very well get into your lungs.
Do you live near any type of fertilizer plant? Or something similar? Its most likely an environmental factor playing a roll in you lung issues.
Since youre over 40 it could even be asbestos related.
Last nail in the coffin... nitrogen is the majority of our air, and is a key nutrient in alot of things life cycles, and we breath it in every day in higher doses than we give our plants.... so for there to be chemicals, that are similar to the ones you are feeding your plants, in the fluid in your lungs, it is not a surprise to me because they are most likely in the air you breathe every day.
No disrespect is meant in this reply, just facts.