There is robust data that the risk of first-hand smoke is not a linear relationship between cancer (and other bad stuff) and dose--no amount of smoking is safe.
To be frank you are uninformed on basic statistics as well as medicine.
You are doing the standard thing that many educated people do when they think they are smarter and more informed than they are. You dress up a bad take as if you found some secret (CDC's hypocritical language) and assume that a mathematical relationship exists ("obviously exposure to bad stuff carries linear risk"), when it is actually more complex than that (if we can call a binary relationship more complex than linear lol).
This is a straw man. I believe that a lot of stuff carries continuous risk going up from zero and increasing with dosage.
If a substance does not start with zero risk at zero dose, it is most likely not a toxin but an essential (i.e. vitamin A).
Very few substances are so rare that the discreteness might matter for practical purposes.
To portray the risk as binary, centered at zero is certainly wrong. You also would have a very hard time to find study subjects who have never been exposed to a few particles of smoke.
To be frank you are uninformed on basic statistics as well as medicine.
You are doing the standard thing that many educated people do when they think they are smarter and more informed than they are. You dress up a bad take as if you found some secret (CDC's hypocritical language) and assume that a mathematical relationship exists ("obviously exposure to bad stuff carries linear risk"), when it is actually more complex than that (if we can call a binary relationship more complex than linear lol).