I have zero medical training, I took High School Biology in about 1979/1980, so much of what we were taught could even have been superseded by now.
But I adhere to a theory that many do, that cancer has more to do with genetics than environment, it is definitely something you can inherit, but even that is no guarantee. I've known people 90+ who smoked multiple packs of cigarettes a day who have no lung cancer while others get it in their 20s or 30s. Again, I'm making generalizations and assumptions with no formal education on the subject. But observation is a core component of the scientific theory. I just spent all of my science credits in college on Astronomy
Do not take this to mean that I eschew safety equipment, or in the case of toxic chemicals even basic common sense. Do not play with guns, run with scissors, play golf in a lightning storm, or tempt fate in any way. I wear a real respirator (change the cartridges regularly based on use) and have the garage door open if I am spraying lacquers or enamels, and if the acrylic session will be long I open the door, which sucks in Texas summers.